Guide to surveys and inspections of buildings and associated structures

The Institution of Structural Engineers International HQ 11 Upper Belgrave Street London SW1X 8BH United Kingdom T: +44 (0) 20 7235 4535 F: +44 (0) 20 7235 4294 E: [email protected] W: www.istructe.org

Guide to surveys and inspections

This Guide is for the benefit of Engineers and Surveyors already familiar with inspecting, appraising and reporting upon buildings and associated structures. It is an update of the popular Guide to surveys and inspections of buildings and similar structures and provides guidance on the overall methods to the approach and reporting of inspections, including the safety and legal considerations surrounding them. Moreover, extensive checklists are provided to give on-site support whilst carrying out an inspection. The document is a succinct and handy pocket-sized guide for use before and on-site during an inspection/ survey; it is ring bound for ease of use and printed on durable, water-resistant paper.

IStructE

Guide to surveys and inspections of buildings and associated structures

Guide to

Surveys and inspections of buildings and associated structures June 2008

Guide to

Surveys and inspections of buildings and associated structures June 2008

This publication supersedes and updates the Guide to surveys and inspections of buildings and similar structures (1991)

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Constitution of Task Group B P Clancy FRSA JP BSc(Eng) CEng FIStructE FICE FCIOB MRICS MCIArb FBEng Chairman C D Boydell BSc CEng MIStructE MICE K K S Chan BSc Dipl Eng. MSc CEng MIStructE MCIArb Vice-Chairman W E Lord BSc Dip Law CEng MIStructE MICE Barrister C Mahony BSc MaPS MBIFM MRICS (Representing RICS) A H PercivalCEng MIStructE B Whitehead BEng CEng MCIBSE (Representing CIBSE) J A Wolstenholme BEng CEng FIStructE MICE MIExpE (Representing HSE) Secretary to the Task Group B H G Cresswell Riol BEng Acknowledgement is made to the following for their contribution to the development and review of this Guide: Brian Bell, Angus Cormie, Mark Crosby, John Crowley (RICS), Steve Davies, Tom Edge (CIBSE), Peter Harris, Ashley Johnson, Jo’ Kenward, Deborah Lazarus, Fergus Shaw, Rob Thomas and Bob Wilson. Acknowledgement is also made to the Task Group for the First Edition: Brian Clancy, Roger Johnson, Edward Lovejoy, Michael O’Reilly, Bob Stagg and Donald Wade.

Published by The Institution of Structural Engineers International HQ, 11 Upper Belgrave Street, London SW1X 8BH, UK ISBN 978-1-906335-05-2 Front cover: © www.webbaviation.co.uk © 2008 The Institution of Structural Engineers The Institution of Structural Engineers and the members who served on the Task Group which produced this Guide have endeavoured to ensure the accuracy of its contents. However, the guidance and recommendations given in the Guide should always be reviewed by those using the Guide in the light of the facts of their particular case and specialist advice obtained as necessary. No liability for negligence or otherwise in relation to this Guide and its contents is accepted by the Institution, the members of the Task Group, their servants or agents. Any person using this Guidance should pay particular attention to the provisions of this Condition. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means without prior permission of the Institution of Structural Engineers, who may be contacted at 11 Upper Belgrave Street, London SW1X 8BH.

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Contents 1 Introduction

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2 Definitions of types of surveys

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2.1 2.2

Introduction Definitions

3 Safety considerations 3.1 General 3.2 Health and safety legislation

4 Legal aspects 4.1 4.2 4.3 4.4

Introduction Liability: General principles of English law  Practical measures to minimise the likelihood of a finding of negligence Exclusion, limitation clauses and disclaimers

5  Classification of buildings by construction and use – common associated problems 5.1 5.2 5.3

Common issues Types of building Use of building

6 Assessment of findings 6.1 6.2 6.3 6.4 6.5

Refer back and check the agreed brief Record findings Form an assessment Other points that might be considered Conclusion

3 4

8 8 9

11 11 11 12 13

15 15 16 19

24 24 24 24 25 25

7 Form of report

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8  Suggested reading

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Appendix A Survey equipment

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Appendix B Items for possible consideration during survey work

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Foreword When the first version of this Guide was published by the Institution in 1991, it was unique – and still is. There was no other publication serving the purpose of being both a guide to the surveying and inspection of buildings and structures, whilst at the same time being a very user-friendly ‘on site’ reference. In those respects, this new version of the Guide still serves its original purpose. However, since the first version there have been numerous developments in surveying and inspection techniques, in legal and professional requirements and a greater emphasis on the issues of health and safety relating to them. It is also noted that whenever lectures are run, or courses presented, by the Institution on the broad topic of inspecting, surveying, appraising, reporting on, maintaining and modifying existing buildings and structures, they always attract large audiences from across the building industry. The topic remains both popular and relevant, and with the vast majority of all buildings and structures at any one time just standing there deteriorating with no, or minimal, maintenance, is it any wonder? The Institution has therefore decided to publish a new version of the Guide to incorporate the latest thinking on the topic. Buildings and structures are becoming ever more complex, requiring broader based skills and greater knowledge to really understand them; new materials; glass, stainless steel, geo-grids and others; are now with us and the more traditional materials; masonry, timber, steel and concrete; are being used in more innovative ways. Also because a building is old and has stood the test of time it does not necessarily mean it is well-built, as with all buildings care should be taken to look for tell-tale signs of defects. At the same time it is recognised that Structural Engineers are not the only building industry professionals that possess and offer inspection and surveying skills and services to those requiring them. With these thoughts in mind, in order to avoid duplication of effort by other professional bodies and, consequently, the existence of similar publications serving virtually the same purpose but with sometimes conflicting emphasis and advice, this new version of the Guide has had the blessing of the RICS and CIBSE to involve their members in its drafting and appraisal. That in itself is again probably unique. This does not mean that IStructE, RICS and CIBSE members are expected to be familiar with all aspects of the Guide, but that they should at least recognise the spectrum of topics that exist and IStructE Surveys and inspections

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that may well contribute to a competent surveying and appraisal exercise; they can therefore be aware that specialist advice may be required on those topics that are not within their personal experience and competence. My thanks to all members of the Task Group who helped to research and draft the Guide and to their respective professional bodies for encouraging participation in the drafting of this very worthwhile publication.

BRIAN CLANCY Task Group Chairman

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1 Introduction This Guide is for the benefit of Engineers and Surveyors already familiar with inspecting, appraising and reporting upon buildings and associated structures. Engineers undertaking this type of work will be expected to be generally aware of current knowledge and practice relating to the matters upon which they are offering advice. Where reference is made to Engineer it is meant to refer to a qualified Structural Engineer or any other competent professional, such as a qualified Building Surveyor, undertaking this work. The scope of work comprising a structural inspection or survey can vary greatly. It is therefore important that the Engineer advises and agrees with the client the precise nature of the survey and the scope of work to be carried out; this is discussed further in Chapter 2. This Guide covers the basic approach which should be adopted by Engineers undertaking inspections and surveys of buildings and associated structures. Experienced and conscientious Engineers will be expected to use their skill to identify the items which could result in significant problems or unusual maintenance costs in the short and long term. When inspecting buildings and structures for such purposes as determining structural adequacy or general condition there is a multiplicity of items which should be examined and it is virtually impossible for an Engineer, no matter how competent, to cover everything that could be checked during such an operation. Points which are ‘missed’ can go unnoticed, not because the Engineer is unaware of such items, but because those particular items were not specifically checked at the time. It should be emphasised that, when inspecting an existing building, it is not realistic to assume that each and every defect which exists within that building will be identified. It is important that the client be informed of the limitations of the exercise which is being carried out. The Engineer who undertakes a survey is expected to exercise the skill and care of a reasonably experienced and competent Engineer. The law recognises that perfection is unattainable and hence does not impose liability simply because the Engineer fails to make a perfect diagnosis. Items for possible consideration during site work are illustrated in Appendix B. The list is not to be considered exhaustive and Engineers may wish to include additional items from their own experience, such as particular characteristics of buildings and

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substrata peculiar to their region or area of the country. Equally the Engineer may decide to exclude other items. Appendix B is not intended to provide an instrument for Engineers unfamiliar with surveying and inspection to ‘learn the art’; it is an aid for those already familiar with the procedures. Specialist advice may be required over and above the expertise which the Engineer might possess on items such as plumbing, heating, electrical installations and similar subjects. Engineers asked to advise on these subjects should make the limitations of their expertise clear and recommend additional specialist advice if this is thought to be necessary. The Institution and other professional bodies have over the years produced a number of publications dealing in detail with the appraisal and inspection of buildings and structures, and for the assessment of the stability and structural adequacy of buildings. For more detailed information reference should be made to such documents, particularly Appraisal of existing structures and the other publications listed in Chapter 8. Where mention is made to legal references and precedents these are related to the law in England and Wales, but the principles with respect to surveying and inspection may be applicable to other countries.

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2  Definitions of types of surveys

2.1

Introduction

When carrying out a survey, the first priority is to clarify and agree with the client the scope of the survey and subsequent report. Failure to do so could result in the client receiving a survey report which fails to answer the original requirements or the Engineer’s efforts may be misdirected and consideration given to issues which are of no interest to the client or which potentially opens the Engineer to unnecessary liability. A written brief, clearly stating the scope of the survey, is important and it should be written in terms understood by both parties, i.e. the client and the Engineer. Since the first edition of this Guide in 1991, a number of different types of inspections/appraisals/surveys have been identified and defined. The most recent compendium of these surveys and their definitions is contained in the RICS Guidance Note, Building Surveys and Inspections of Commercial and Industrial Property. That document identifies over 30 different types of building industry surveys and inspections. Those most applicable to Structural Engineers are given in the following section; Engineers with a more extensive range of experience and training may consider themselves qualified to undertake a broader range of surveys than those mentioned. When engaged as an expert witness, there are additional duties that the Engineer will need to be aware of which go beyond the scope of this Guide (reference should be made to Expert evidence: A guide for expert witnesses and their clients 2nd ed., IStructE (2003)). The following paragraphs give a brief explanation of commonly used titles as generally defined by BSI (BS 6100: Glossary of building and civil engineering terms) and CIC (Definitions of inspections and surveys of buildings) and slightly adapted at the time to suit RICS requirements. The RICS divide their definitions under four headings; Acquisition, Occupation, Disposal and Development; that is not done here. Although in common use previously, it is now advised that general terms such as structural inspection, appraisal, assessment or investigation should not be used if one of the definitions below would suffice. This avoids confusion in the minds of the public. If a non standard term is used, then it should be rigorously defined at the beginning of the report.

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CIC recommends that the term Structural Survey should not be used, as it is much abused and ill defined.

2.2

Definitions

These are succinct definitions; for fuller definitions refer to BSI, CIC references or the RICS Guidance Note. 2.2.1 Inspection of Buildings Under Construction Inspection of Buildings Under Construction are required for a variety of purposes, including typically statutory requirements and Latent Defects Insurance, which may dictate the frequency and scope of inspection and reporting format; these should be agreed between the professional and the client. (Source CIC) 2.2.2 Building Survey A Building Survey is an investigation and assessment of the construction and condition of a building and it will not normally include advice on value. It may be carried out by a qualified member of a recognized professional body, who has the appropriate experience. The survey will generally include the structure, fabric, finishes and grounds; the exposure and testing of services are not usually covered. (Source CIC) The extent of the survey will be subject to specific agreement between the professional advisor and the client; any advice on costs of repairs will be subject to separate agreement. It will not normally include exploratory or intrusive work. The report will normally only include reference to visible defects and guidance as appropriate on maintenance and remedial measures. The report may recommend that Elemental or Specialist Investigations (see Section 2.2.5) are undertaken or other specialist advice obtained relating to specific issues. 2.2.3 Schedule of Condition A Schedule of Condition will record the condition of the buildings at that particular time and may be supported by photographs, sketches and drawings. It may be prepared at the beginning of a lease or prior to commencement of adjacent construction work or in connection with litigation. Often, a Schedule of Condition forms part of a Party Wall Award. (Source CIC) 2.2.4 Schedule of Dilapidations A Schedule of Dilapidations will identify the wants of repair of tenanted premises in relation to the repairing obligations under the terms of the lease. It may be prepared for service on the

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landlord or tenant, depending on their respective lease obligations. (Source CIC) It is common to include general guidance on how to carry out the repairs required and to include an estimate of the costs. 2.2.5 Elemental or Specialist Structural Investigations Elemental or Specialist Structural Investigations, also known as defects diagnosis/building pathology, will be carried out where concern exists over specific parts of, or defects in, a property. Examples of this specialist work are the detailed study of movement, cracking, bulging, timber decay or the testing of building services such as wiring, heating, drainage, etc. (Source CIC) These may be required to assess the relevance and implications of conditions found within the building or unusual incidents affecting it; they are normally done by qualified Structural Engineers, or suitably experienced RICS or CIBSE members or other professionals. 2.2.6 Home Condition Reports Home Condition Reports may form part of the Home Information Pack (HIP) which is required by law for the sale of domestic property. Engineers undertaking such work may require additional training and the reports’ scope may change in the future. 2.2.7 Material Testing Material Testing (e.g. concrete, steel, timber, etc.) is the sampling and testing of materials found in the fabric of the building as regards their present condition, classification and suitability for the future or continuing use of the building; these tests will include the independent interpretation of test results; they are usually done by specialist firms under the supervision and direction of suitably qualified and experienced professionals (e.g. Structural Engineers, Building Surveyors, etc.). Specialist reports may not be easily understood by a lay-client, in which case, if requested, the Engineer should assist with the interpretation of the information so that the client understands the options available and can decide accordingly. Appointment of such specialist testing and inspecting firms should ideally be by direct appointment by the client and based on the recommendation of the Engineer. 2.2.8 Subsoil investigation and testing Subsoil investigation and testing is required to determine the physical characteristics of sites as they affect the design and IStructE Surveys and inspections

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construction of buildings (or civil engineering works), including the stability of neighbouring structures, subsoil contamination and land features. (Source BSI) 2.2.9 Stock Condition Survey A Stock Condition Survey will normally be commissioned to assess the state of repair or condition of an organisation’s current building stock in connection with the preparation of a maintenance programme. The results of Stock Condition Surveys will often be stored on a database. (Source CIC) 2.2.10 Investigation Prior to Alteration An Investigation Prior to Alteration will sometimes be required when alteration work is to be undertaken on a building. Subject to the necessary authority, it may involve opening up, measuring, calculations to check the adequacy of structural and service elements and detailed tests. (Source CIC) This investigation can be more detailed than the Building Survey (see Section 2.2.2) and is likely to involve the services of a number of specialists (see Sections 2.2.5 to 2.2.7). The scope of this type of survey will be specific to each individual job and, if necessary, the brief may be altered as findings on site dictate. 2.2.11 Feasibility Study A Feasibility Study is an exercise to assess the design and cost implications of a proposed project; the product of which is a Feasibility Report. (Source BSI) 2.2.12 Measured Survey/Dimensional Survey A Measured Survey, sometimes referred to as a Dimensional Survey, will involve taking measurements of a building and/or its site in order to prepare accurate drawings to scale. Such a survey may include taking levels. The purpose for which the drawings will be required, their scale, detail and acceptable tolerances need to be agreed between the parties beforehand. (Source CIC) 2.2.13 Mechanical, Electrical and similar Services Surveys Mechanical, Electrical and similar Services Surveys may be required to assess the condition of existing services and their compliance with both legislation and industry standards (e.g. Building Regulations Parts L2A and L2B) for both existing and any future proposed usage – these are usually carried out

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by CIBSE members or suitably experienced and qualified tradesmen. 2.2.14 Other types of survey Definitions of other types of surveys and inspections not dealt with in this Guide include (for definitions refer to the RICS publication): • access appraisal • access audit (Disability Discrimination Act (DDA)) • asbestos inspection • BREEAM assessment • disaster recovery risk assessment • due diligence • environmental assessment • fire risk assessment • fire/storm/water damage inspection for insurance purposes • glass/glazing assessment • health & safety audit • latent defects insurance • life cycle costing • local authority ceilings inspection in public places • planned maintenance inspection • reinstatement cost assessment for insurance purposes • workplace assessment.

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3  Safety considerations

3.1

General

When planning a survey for the purpose of investigating a part or the whole of a structure at the start or during the progression of a project, or for use as part of an overall programme of asset management, account should be taken of the: • type of premises • existing knowledge of structure • degree of risk/hazard for conducting the survey • method of investigation – including necessary equipment and clothing (Appendix A). If work is carried out alone, a system of reporting-in at specified intervals should be adopted. In general investigations should not be carried out by inexperienced people working on their own. Dilapidated or damaged buildings and confined spaces usually constitute a particular hazard. Where a building has been empty for some time and/or allowed to deteriorate more generally, parts of the structure may have become unsafe (e.g. rotten timber floors). Health hazards may exist typically owing to the build up of animal droppings, contamination, decomposed carcases, dust from previous activities, concentration of gases, discarded needles, etc. Defective, redundant or unmaintained building services (i.e. gas, electric, water, sewerage) may in themselves present a hazard. Areas of some buildings may have been used by squatters or have been vandalised with a subsequent effect on the structure. Before entering a building an assessment of potential hazards should be carried out for the particular tasks (see Section 3.2), and a general assessment of the state of the structure should be made and recorded. Only when satisfied that it is reasonably sound or temporary works are in place should entry be made. Each successive stage where physical or material properties change, the state of the structure should be reassessed before proceeding. If any part is thought to be unsafe, all reasonable steps should be taken immediately by the Engineer to deter access until such time as it is made safe or an alternative safe method can be used. The Engineer should discuss with the client what action should be taken, and inform him that the building owner should be told or at least the Local Authority informed if there is imminent danger. Engineers should always remember their public duty with regard to the health and safety of others.

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Although the client’s brief and the assessment will probably be specific as to the requirements of the investigation, nevertheless when undertaking the survey it is necessary to comment on matters of immediate danger to health and safety, even outside the brief, where the exercise of expertise would normally be expected. The Engineer should refer to the HSE website (www.hse.gov.uk) or other sources on other health and safety regulations or guidance which may be relevant to the survey work to be undertaken.

3.2

Health and safety legislation

In the UK the Health and Safety at Work etc. Act 1974 (HSWA) lays out the general duties of every employer, including persons concerned with premises. The Act requires them to: ‘…ensure, so far as is reasonably practicable, the health, safety and welfare at work of all his employees.’ (Section 2(1)) ‘…ensure, so far as is reasonably practicable, that persons not in his employment who may be affected thereby are not thereby exposed to risks to their health or safety.’ (Section 3(1)) Under Section 4 of the Act those persons who have control of premises are required to: ‘…take such measures as it is reasonable for a person in his position to take to ensure, so far as is reasonably practicable, that the premises, all means of access thereto or egress therefrom available for use by persons using the premises, and any plant or substance in the premises or, as the case may be, provided for use there, is or are safe and without risks to health.’ (Section 4(2)) Other duties which may affect employers and employees are set out in the remaining Sections 2 to 9 inclusive of HSWA. Other employers and self-employed personnel on the site other than the Engineer’s direct employer may have responsibility for the safety of the Engineer. These may include the building owner or any contractor undertaking work in the building. Engineers should also be aware of their responsibility for their own safety and the safety of others under Section 7 of the Act. The employer is also required under Section 3 of the Management of Health and Safety at Work Regulations 1999 (MHSWR) to carry out health and safety risk assessments in relation to all employees who are exposed to hazards in the course of their work and to third parties who may be exposed as a result of the work being carried out. However, Engineers should always carry out, update and reassess their own confirmatory risk

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assessment and may consider recording significant findings or ‘no changes required’. The following principles of prevention should also be applied by virtue of Regulation 4 and Schedule 1 in MHSWR: a avoiding risks b evaluating the risks which cannot be avoided c combating the risks at source d adapting the work to the individual, especially as regards the design of workplaces, the choice of work equipment and the choice of working and production methods, with a view, in particular, to alleviating monotonous work and work at a predetermined work-rate and to reducing their effect on health e adapting to technical progress f replacing the dangerous by the non-dangerous or the less dangerous g developing a coherent overall prevention policy which covers technology, organisation of work, working conditions, social relationships and the influence of factors relating to the working environment h giving collective protective measures priority over individual protective measures i giving appropriate instructions to employees. The above principles of prevention have been carried forward into the Construction (Design and Management) Regulations 2007 (CDM) and the Engineer needs to ascertain how CDM 2007 affects the undertaking of the specific works. Refer to CDM 2007 Regulations and ACoP L144 for further guidance. Recognition should also be given to work in high hazard areas where other specific regulations are applicable. Further guidance should be taken from Part 4 of CDM 2007 regarding hazards on site.

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4  Legal aspects

4.1

Introduction

The intention of the advice in this Guide is to help Engineers prepare a satisfactory report for the client which conforms, as reasonably as possible, with the requirements of the brief. However, Engineers should also be aware of their legal responsibilities and these are outlined in the following sections. The law changes regularly and Engineers should try and keep up to date with major changes.

4.2

Liability: General principles of English law

Under normal circumstances, the appropriate standard of care will be the skill and care reasonably to be expected of a competent Engineer performing a survey of the type in question. Engineers performing a survey may be liable to the client for any losses which the client incurs as a result of incorrect conclusions or recommendations in, or omissions from the survey report provided that such conclusions, recommendations or omissions are a result of the Engineer’s negligence and/or breach of the terms and conditions of appointment. Negligence in this context means a failure by the Engineer to exercise the appropriate standard of care. Engineers should take great care to ensure that they do not hold themselves out or accept terms of appointment as a specialist for a particular type of survey otherwise they may be measurable to a higher standard of care; unless the Engineer has a particular specialist skill (e.g. specialist expertise in historic buildings) and intends to exercise this specialist skill in the particular survey or appraisal. An Engineer who carries out a survey may be negligent because of a failure to exercise reasonable skill and care at any stage in the production of the report, including negligent planning of the survey, negligent site observations, negligent recording and analysis of data, negligent writing and checking of the report and failure to recommend specialist surveys. As a direct result of the law of contract, an Engineer is normally only liable to the person or client for whom the report is prepared. A third party cannot normally rely on the report unless the Engineer knows of the existence and interest of that party at the time of production of the survey report and the report is being produced in the expectation that such a party will read and rely upon its contents. This is particularly relevant where the survey concerns a domestic dwelling and is commissioned by a building society but where the prospective purchaser pays indirectly for IStructE Surveys and inspections

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the survey; in this situation the Engineer will normally be liable to the prospective purchaser for any losses which the purchaser sustains and which are directly attributable to the advice given in the report. In some cases, the Engineer may be asked to re-address the report to a named third party so that it may be relied upon by someone other than the commissioning client. Particular care should therefore be exercised by the Engineer when re-addressing reports especially as the interest and requirements of the client and the named third party may not be the same. In other situations, third parties may be entitled to enforce the terms of the appointment and therefore rely on the report by virtue of the Contracts (Rights of Third Parties) Act 1999. Even if a third party cannot rely on the report for pure financial losses such as diminution in value of the property, an Engineer may still be liable, in tort, to that party if the property is physically damaged as a result of the Engineer’s negligence. An Engineer performing a survey may also be liable in tort to all persons who are physically injured or whose property is damaged by their actions in carrying out the survey or as a result of the negligent survey – provided that the injury or damage is reasonably foreseeable at the time of the survey as a likely consequence of such actions or negligence. The Engineer may also be pursued for breach of statutory functions or duties. This is particularly relevant in the realms of health and safety. Engineers undertaking a survey should ascertain that they are adequately insured for this work (whether personally or through their employer) and that any action taken or report written in connection with the work complies with the terms of their insurance policy (see also Merrett v Babb case mentioned in Section 4.4). If in doubt, written advice of the insurer should be sought concerning the context and degree of cover.

4.3 Practical measures to minimise the likelihood of a finding of negligence Engineers should set out the intended scope and purpose of their appointment in writing at the time of appointment and should, where possible, see that this is agreed with the client. The scope and purpose should then be included either as an appendix to or repeated in the text of the report along with the Engineers standard terms and conditions of engagement. This provides clarity within the report as to what the Engineer was engaged to do.

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A survey checklist should be compiled and used during surveys. It should enable the Engineer to indicate both the accessibility of each element of the structure and the level of detail of the examination performed on each element. The proper use of such a list indicates to a court or other tribunal that a satisfactory system of working has been employed and that care and professionalism have been exercised. This Guide is intended to form the basis of such a checklist and Engineers should in any event tailor the checklist to suit their own specialist knowledge and experience and to the property to be surveyed. When making recommendations the Engineer should, if appropriate, explain any shortcomings in the data upon which this advice is based. The Engineer should indicate whether and to what extent unforeseen circumstances might make a reassessment of this advice necessary. Qualifications of this nature not only provide the client with more honest advice, but also make it more difficult for anyone, client or third party, to misinterpret the report. If the Engineer’s opinion is that the condition of the building’s structure or its future movement or deterioration cannot be accurately predicted it should be stated and, in appropriate cases, the client should be advised to seek advice from an insurance firm regarding the viability of insuring against future possible structural damage Engineers should be careful not to tender advice they are not qualified to give. Any necessary statements concerning, for instance, legal or insurance matters or specialist technical elements should only be made in the broadest possible terms and should be accompanied by recommendations to seek advice from suitably qualified consultants or firms. Engineers should also be aware of the Institution’s Guidance Note 3 – Checking and appraisal/review when reviewing the work of another Engineer.

4.4

Exclusion, limitation clauses and disclaimers

Engineers may wish to exclude or limit their liability to the client for financial loss or damage to property. This can be achieved by including clauses in the agreed terms of appointment. There is statutory protection for clients against unfair contract terms, particularly where the client is a consumer. Exclusion or limitation clauses will only be effective if the Court considers them to be reasonable. Engineers may seek to exclude liability to persons other than the client and to whom they may owe a duty of care by the use of a prominent ‘disclaimer’ in the report. When such a duty of care is IStructE Surveys and inspections

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owed to a third person the use of a disclaimer is only effective if the Court also considers the disclaimer to be reasonable. Whether an exclusion clause or disclaimer is reasonable depends on a wide range of factors including the relative commercial bargaining power of the parties involved, the use of standard terms and conditions and the possibility, or otherwise, of obtaining adequate insurance cover. It will normally be difficult for a firm of engineers to successfully exclude or disclaim liability against owners or buyers of modest domestic properties. Liability for fraudulent concealment, personal injury or death resulting from negligence can never be excluded, limited or disclaimed. Following the decision in the case of Merrett v Babb, an individual Engineer may be found personally liable where insurance cover is not maintained by the employer. This particular case, which some consider to be peculiar on its facts, has been taken sufficiently seriously by the RICS that a Member Support Service Levy designed to provide support in appropriate circumstances was set up. In the absence of such a service from the Institution, members may consider including a similar exclusion clause to that which may be found in the ACE standard conditions in the terms of their appointment stipulating that the client will only look to the employer for recompense (and not to the individual) if there is a finding of negligence. In order to reduce the likelihood of such a clause being deemed ineffective by the courts for unreasonableness, the Engineer may also consider bringing such a clause to the specific attention of the client and attempting to explain why such a clause is required.

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5  Classification of buildings by construction and use – common associated problems

5.1

Common issues

Buildings and structures constructed for a particular purpose or predominantly from one specific structural material often have defects peculiar to that material, age of building and type of construction. This Chapter classifies the more common buildings by type of construction and by use, listing the most frequent problems which affect them. It is implicit that the Engineer is sufficiently experienced to understand the assembly of the building, how the components interact and the way in which overall stability is maintained. Such experience should allow the Engineer to understand the building and draw conclusions from its general condition, crack patterns and distorted form, where evident. Remember that apparently similar signs of damage may have different causes. There are problems/issues which may occur in all types of buildings, some of which are summarised below to avoid repetition. • Understand load path and overall stability. • Soil related (e.g. subsidence, settlement, heave, ground slip, trees, etc). • Ill considered or incompatible alterations (e.g. structural, services, etc). • Misuse/overloading/vandalism. • Structural instability and local lateral instability. • Poor detailing. • Age and quality related deterioration. • Poor workmanship/construction. • Poor/no maintenance. • Damp and water penetration (e.g. rising damp, penetrating damp, condensation, leaking services, etc). • Flat roofs and water ponding problems. • Support for renewable energy systems (e.g. solar panels, photovoltaic, wind turbines) – design and condition. • Thermal movement. • Material decay (e.g. timber rot, infestation, etc). • Progressive collapse – Building Regulation Schedule 1 Part A3 issues. • Balustrade, balconies and parapet inadequacies. • Access difficulty for inspection, maintenance and repair. • Outdated services. IStructE Surveys and inspections

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• • • •

5.2

Change of use factors (e.g. loading, thermal performance, etc). Drainage problems. Potential damage from adjacent building works. Smoke/fire/fume transmission.

Types of building

5.2.1 Loadbearing masonry a Weathering and softening of mortar. b Use of inappropriate mortar. c Inadequacy of lintels over doors and windows. d Inadequacies in bay window construction or replacement. e Delamination of brickwork, stonework or rendering. f Parapet and balustrade walls – lateral stability to resist natural elements and crowd loading. g Masonry tie failure (e.g. cavity walls, parapet copings, cladding panels, etc). h Hidden ducts and flues in walls. i Solid walls (pre-circa 1920) and rubble filled walls (pre-circa 1860 and be aware of regional usages). j Roof spread, lateral tying, inadequate anchoring – vertical and lateral, also stability and distortion of chimneys. k Cracking of calcium silicate and other forms of autoclaved concrete-brick manufacture. l Masonry unit issues (e.g. mundic concrete blocks, underfired clay bricks, etc). m Problems with bulging of walls (e.g. lack of lateral restraint, wall tie failure, chemical attack, sulfates, hard repointing, overloading, settlement of infill, etc). n Rotational distortion and lateral displacement due to eccentric loading. 5.2.2 Concrete framed a Movement and jointing problems – adequacy of bearings, fixings and infilling, especially for precast units and frames. b Lack of cover to steel reinforcement/rebar corrosion. c Cracks around column heads – particularly signs on top surfaces of structural flat slab construction – column head shear failure – sudden progressive collapse. d Diagonal cracks – in beams where they frame into columns. e Cladding and fixings displacement or failure. f Spalling – may be due to movement or corrosion. g Adequacy of fireproofing – concrete cover to the reinforcement.

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h Use of suspect materials (e.g. HAC, woodwool formers, etc). i Corrosion of tendons in prestressed units. j Suspended floor slab problems (e.g. inadequacy of bearings, continuity, etc). k Prestressed floor units with hogging or sagging profiles along their length. l Prestressed floor units with inadequate lateral shear keying. m Fixings into and misuse of prestressed units. n Specialist patented system problems. o Buried members (foundations and ground beams – possible acid/sulfate attack, etc) – provide an overview based on quality of visible superstructure. 5.2.3 Steel framed As for concrete framed generally plus: a Does the cladding contribute to stability? b Bracing and buttressing and use of movement connections. c Corrosion of members within external walls, at bases, at bearings, in hidden voids, etc. Requires investigation? d Welding and bolt failures and omissions (e.g. weathering, contamination, damp ingress, etc). e Defects or poor workmanship in connections (e.g. severe rusting or pitting, cracked welds, bolt or rivet omissions or replacement, distortion or buckling of the whole connection, effectiveness of HSFG bolts, etc). f Removal (or lack) of stability members (e.g. cross bracing, infilling wall panels, etc). g Defects in fireproofing (e.g. concrete, dry casing, damage to intumescent paints, etc). Use of asbestos. h Effects of roof, gutters and cladding leaks – bimetallic action. i Possible corrosion inside hollow sections. j Externally exposed steel and connections (e.g. paint, impact damage, difficult maintenance access). k Adequate protection of buried sections. 5.2.4 Wrought iron members Wrought iron, a structural material generally used between 1880 till 1905, may be difficult to distinguish from steel on site. It is closer in behaviour to steel than to cast iron, thus many of the points raised in Section 5.2.3 also apply to wrought iron.

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5.2.5 Cast iron members a Columns – evidence of eccentric loading or lack of verticality. Eccentric hollow cores. Susceptibility to vehicle or other impact damage. b Beams – evidence of sections being used in bending (e.g. lintels, brackets, beams or arches). Record the details of the cross section. Are point loads applied? Is loading eccentric? Loads hanging from bottom flange. c Loads hanging from cast iron beams. d Stability of jack arch floors. e Attempts at welding or other non-original fixing onto members. f Use of hollow cast iron columns as rainwater pipes. g Parapet and balustrades – lateral stability to resist natural elements and crowd loading. h Buried members (foundations, ground beams, basement conditions, etc) – provide an overview based on quality of visible superstructure. i Evidence of reuse of structural elements. 5.2.6 Timber and timber framed a Difficulty in assessing the quality of the timber and its degree of seasoning. b Appropriate species? c Wet and dry rot; beetle attack – effects on structural capacity. d Members built into masonry, particularly external walls – damp issues. e Ends of columns, props, built-in beams and joists may be suspect. f Understanding loadpath and stability – modifications, members removed. g Tension members and their fixings/connections. h Overloading and deflection of timber floors – but consider the relevance. i Tendency for old timber sections to appear overloaded by current design requirements – but consider the relevance. j Load sharing issues. k Shakes, splits, knots and deflection effects. l Drying shrinkage problems. m Distortions due to atmospheric conditions and long term loading – is service class 3 (wet exposure) appropriate? n Structural and operational relevance of distortions. o Service holes, notches, etc, cut through sections and DIY repairs.

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p Flitching and other strength enhancements. q Softwood modifications to hardwood framing. r Adequacy of multiple sections – bolting, gluing, patent connections, etc, including long term and atmospheric effects and temperature. s Failure or modification of adjacent stability members (e.g. floors, joists, etc). t Preservation treatment – relevance, adequacy and suitability. u Charring of retained members subjected to fire. v Buried members (foundations, timber piles, ground beams, basement conditions, etc) – provide an overview based on quality of visible superstructure. 5.2.7 Large panel systems a Disproportionate collapse issues. b Integrity of joints between panels (including gaskets, fixings, etc). c Smoke/fire/fume transmission. d Typical reinforced concrete problems regarding durability. Condensation or damp penetration effects. Note that in certain circumstances glazing and structural glass, like cladding and sheeting, may be part of the structure and should be considered accordingly.

5.3

Use of building

5.3.1 Residential a Party wall (Party Wall Act especially relevant to alterations or repairs including underpinning) and shared elements. Shared liabilities (e.g. roofs, drains, foundations, distant gable walls, etc). b Fire/smoke/fume hazards. c Lack of party walls within roofs. d Building Regulations approval for alterations. e Noise transfer between properties. f ‘Book End’ effects. g Basement leaks. h Subsidence and heave – including lateral heave. i Proximity of trees. j Ground floor slab problems – see Section 5.3.2b.

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5.3.2

Commercial and Industrial (see also common

problems and type of construction)

a Vibration of long span floors. b Floor slab – suspended or on solid/treated ground. Typical problems – overloading, settlement, adaptations to carry increased load, inadequacy of sub-stratum treatment, etc. c Attrition of structure (e.g. wear in roadways, stairways, etc). d Vehicle impact and traffic effects (e.g. damage at joints). e Lift shaft structural condition and fixings. f Presence of asbestos. g Energy conservation (e.g. Building Regulations Part L2B). h Basement leaks. 5.3.3 Swimming pools and sports halls a Chemical attack on structural elements. b Damp atmosphere problems (e.g. deterioration of timber laminates, metal connections, etc). c Loose tiling. d Leakage through structure of pool. e Defective plant and services. f Large span roofs (e.g. sag, ponding, waterproofing, drainage). g Stress corrosion cracking. h Lack of maintenance, access difficulties. i Grade of stainless steel in ceiling voids over pool. j Corrosion of metalwork above pool. Useful reference: Small Public Indoor Pools, Sports Council (1994). 5.3.4 Hotels and hostels a Difficult access to services and roofs. Modification to the structure to allow for services. b Old premises often extensively modified (e.g. fire resistance, sound proofing, etc). c Vibration of dance floors, overhead lighting, etc. d Balconies, balustrades and walkways. e Stability of unusual structural forms. f Basement leaks.

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5.3.5 Shops and shopping centres a Localised overloading (e.g. stockrooms at Christmas, etc). b Removal of walls and stability elements. c Vibration of long span floors. d ‘Book End’ effects. e Basement leaks. 5.3.6 Cinemas/theatres a Fly tower equipment – wear and tear/alterations. b Stage – wear and tear/alterations – temporary staging. c Seat fixings – old, non standard/compliant, stock not modified, no anchorage available. d Steps and staircases – old, non standard/compliant, etc. e Barriers and handrails – old, non standard/compliant, etc. f Alterations to emergency equipment/lighting/exits, etc. g Ill-considered structural alterations. h False ceilings and lath and plaster linings – licensing certificate. i Scenery erection and movement and associated vehicle loads. 5.3.7 Old and listed buildings a Permission for access and investigations? b Any planning and conservation restrictions on inspection and repair strategy? c Appropriate approvals for alterations? Is this for past or planned works? d Inconsistency in quality and size of structural elements. e Incompatibility of past remedial works. f Long term deterioration due to environmental factors (e.g. weather, pollution, etc). g Deterioration in structural robustness. h Hidden framing or bonding members (e.g. timber, iron, etc). i Inadequate and ill defined foundations – implications. j Vulnerability of cast iron elements. k Basement problems. l Water ingress.

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5.3.8 Industrial/commercial chimneys a Stability – foundations, guying, bowing, etc. b Deterioration at height and inside – due to sulfate, acid, weather, etc. c Pointing, cracking, banding, etc. d Liners – internal spalling and corrosion of mild steel flueway. e Statutory inspections. f Lightning conductors – effectiveness. g Condensation in and drainage of flues. 5.3.9 Places of worship a Towers and spires – stability, dynamic loads (bells), bursting, lightning conductors. b Unusual and/or ancient structural forms. c Roof spread – no lateral tying. d Settlement/subsidence. e Corrosion of steel glazing bars. f Deterioration of hidden timber wall plates and ends of ties and rafters. g Severe weathering and/or delamination of stone masonry. 5.3.10 Agricultural a Reduced safety factors, lower construction standards, DIY and make-shift construction – generally less robust buildings. b Corrosion and pollution from chemicals and waste products. c Overloading/misuse/lack of maintenance. d Lack or removal of bracing. 5.3.11 Car park structures a Vehicle impact damage, access ramps, columns, barriers, etc. b Condition/height of external barriers, parapets, headroom. c Chemical attack to steel/concrete (e.g. waterproofing, road salt, fire damage). d Punching shear around column heads. Large span construction. e Parapet fixings through slab leading to water paths. f Structural and non-structural joints. g Lack of maintenance of drainage systems/damp and saline conditions. h Chemical spillage.

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Useful references: • Design recommendations for multi-storey and underground car parks 3rd ed., IStructE (2002) • Enhancing the whole life structural performance of multistorey car parks, ODPM (2002) • Inspection and maintenance management of car par structures, ICE (2002). 5.3.12 Hospitals/health organisations a Floor vibrations. b Local overloading. c Previous alterations – particularly in relation to building services. d Chemical spillage. 5.3.13 Schools a Load bearing capacity of floors/use – gyms/assembly/library/ laboratories. b Noise separation. c Security/vandalism. d Maintenance (e.g. roof drainage, etc). Schools present a particular environment which may have user hazards that might not be considered as such in an adult environment. Specialist advice may be required. 5.3.14 Tall buildings Many of the considerations covered in this Guide also apply to tall buildings, which for the purposes of this Guide tall buildings are of about five or six storeys and/or of moderate occupancy. The buildings also have further specific issues to be considered which are dealt with in other publications (e.g. Safety in tall buildings and other buildings with large occupancy, IStructE (2002)).

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6  Assessment of findings

6.1 • • •

• •

6.2

Refer back and check the agreed brief Are the requirements of the client fully appreciated? Do the findings give sufficient information for the Engineer to make an assessment to answer the brief? Does the brief need to be extended in view of the findings, e.g. unforeseen circumstances, changes in the client’s requirements, further investigations, need for monitoring, etc? Are any specialist reports required to enable the Engin­eer to satisfy the requirements of the brief? Is there any historical information available relating to the structure?

Record findings (Appendix B may be used as an

aide-mémoire)

The site recordings usually take the form of notes, tape recordings, photographs, etc. Consider how the information is stored, and how easy will it be to access in the future. Engineers should try to maintain their records in such a manner that they can be consulted in the future. Engineers should be aware that in court proceedings the recording of the findings during the survey may be called upon to demonstrate the standard of care of their work. It is particularly important to record details of information/ evidence (notes, photographs, sketches, etc; the precise dating of which may be useful) which may later be available for inspection. It should be noted that some evidence is, on occasion, inevitably destroyed during the investigation pro­cess. It is important to note the limitations of the survey (e.g. access, safety considerations, etc.).

6.3

Form an assessment

The assessment should be the logical conclusion of the findings. List the alternative likely causes of a particular defect and give an opinion, if possible, as to which of these items could be considered relevant. A similar approach is advised when recommending possible options for solutions. Engineers should avoid giving authoritative opi­nion on subjects not within their professional training and experience. Instead, Engineers should consider pointing their client towards appropriate specialist help.

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Consideration should be given as to whether structural calculations are necessary to satisfy the requirements of the brief. Engineers should consider whether the issue should involve third parties; such as insurance companies, statutory authorities, etc.

6.4

Other points that might be considered

Where there is concern that immediate action is required to guarantee structu­ral stability, safety, etc. these should be notified im­mediately to the client, and if necessary permission obtained to notify other relevant parties (e.g. the building owner, the Local Authority, etc.). If specifically required, a sufficiently experienced Engineer may give an assessment of the likely costs involved in temporary and/or final remedial works, bearing in mind any statu­tory constraints (e.g. listed building, etc.). It might be advisable to express this as a range of costs. Sometimes it will be more appropriate to recommend that the client seeks advice from a building surveyor, quantity surveyor or contractor. The Engineer should consider whether any additional information should be given which may be outside the brief, but has come to light during the investigation. An example could be when the Engineer is asked to prepare a Schedule of Condition Report in one part of the building, but has found timber infestation in another part of the building. If the Engineer considers the information to be of sufficient structural importance, it may be appropriate to inform the client under a separate report. Engineers should remember that they are responsible for all the advice they provide.

6.5

Conclusion

The Engineer should come to a conclusion based on the assessment of findings which succinctly but comprehensively answer the client’s brief. The Engineer may wish to discuss and explain these conclusions with the client, particularly if there are any contentious issues, before preparing the written report. Whilst certain points in the report might be rephrased, added, even omitted at the request of the client, any opinions expressed must be comprehensively those of the Engineer alone. The Engineer should note that a survey or assessment on compliance of an existing building with regard to the current Building Regulations (e.g. Parts L2A and L2B) can be a very complicated and time-consuming exercise. The Engineer will IStructE Surveys and inspections

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normally be part of a team carrying out this assessment and specialist advice may be required. Note that some specialist industries (e.g. offshore, nuclear, etc.) may have their own procedures for compliance/non-compliance surveys. When inspecting older buildings the Engineer should remember that they may have been designed and constructed to the acceptable standards of their time, and that these may vary from present day standards.

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7  Form of report For most surveys, the written report is the ‘final product’ and is the only tangible evidence the client possesses. It is important to employ care and expertise in its preparation so that the client can obtain the maximum benefit from the survey work carried out. Clearly each survey and subsequent report will be unique but several basic considerations apply generally and the following format is suggested as suitable for most surveys and structural inspections or appraisals. Standard phrases or paragraphs may be helpful in the preparation of the report but there are both risks and advantages in using them. They may act as a ‘checklist’ to see that all points have been reviewed, but care should be taken to ensure that such paragraphs have been properly considered for inclusion and, to that extent, are relevant for the survey carried out. Inclusion of irrelevant standard paragraphs may be used against the Engineer to show that little thought went into the production of the report. Engineers may therefore wish to consider optional inclusions, deletions or modifications for their standard paragraphs to demonstrate that clauses were chosen for inclusion in the report. The document should be suitably bound and be businesslike in appearance. If a large amount of technical information is to be included, appendices could be used. Suitable photographs, layout plans and elevation sketches may assist in illustrating comments made in the text and these can best be included as an appendix which could be bound separately for ease of reference. The following sections are presented as one possible format for a report, with brief explanatory comments. There are of course alternative formats for reports. In a straightforward building survey, say on an average size family dwelling, a simpler report may be quite adequate. Whatever format is chosen, the report should satisfactorily answer the brief and be written in such a manner that it will be clearly understood by a client who may not be familiar with technical terms. As far as possible write in plain English that anyone can understand. For Home Condition Reports the recommended standard format should be followed. Front cover This should include the title of survey and full address of property involved, name of client, name of Engineer and date of report.

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Contents page This is useful if the report is of any significant length and the client may wish to read it selectively. Synopsis/Executive summary A synopsis may be included if the report is too long for the client to read quickly. It can be particularly useful if the client needs to present a summary of the report to a third party, e.g. a local council committee, and should include a summary of the brief, survey procedures and findings, conclusions and recommendations. It should generally be capable of being read in isolation but with reference to the main body of the report. The main messages and recommendations should be written so as to be generally understood by a layman. It is important to emphasise that the synopsis or summary must be read in conjunction with the rest of the report. Important reservations and exclusions should also be included in the synopsis. This section can be bound into the report at the beginning or end or presented separately. The maximum length should be three pages. A synopsis should not contain different information or messages not backed up by information in the body of the report. Introduction The first sub-section should be a clear statement of the scope of the survey as agreed in the brief. The brief should be included or may be reproduced as one of the appendices. Any limitations on the scope of the survey, e.g. time limits, accessibility, etc. should be recorded together with their possible consequences. The date of appointment should also be stated. The second sub-section should state the purpose of the report and include caveats if appropriate. This sub-section should be used to explain the intended purpose of the report as agreed with the client, and state any restrictions on the use and circulation of the report. Any caveats need to be reasonable (see Chapter 4). Two caveats commonly used in reports are to restrict who can rely on the report, and the assumption that the areas investigated are representative of the areas that require inspection. Engineers should also check whether the inclusion of specific disclaimers is required by their insurers. The third sub-section should list the survey procedures undertaken to satisfy the brief. Details of the on-site survey work should be included, e.g. date, weather conditions, etc. Restrictions encountered on site could be stated here.

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Further sections may be needed to cover items such as general description of the building, archival information used, reference to geological maps, etc. Sections dealing with specific topics These are the main sections of the report and would cover specific items within the scope of the survey, e.g. reinforced concrete, structural adequacy, etc. The section should include findings and conclusions, and can include recommendations. Summary of conclusions and recommendations If the report is of any significant length, it is usually appropriate to include a final section to allow the reader to learn of the recommendations without reading all the detail included in the sections on specific topics. It may be that a synopsis will make this section redundant but often the recommendations will warrant more space than will be available in the synopsis. In the conclusions, the reader should always be referred back to the main body of the report for details and further clarification. If the brief requires any specific expertise beyond the competence of the Engineer then this should be dealt with by recommending that the client obtain specialist reports/advice.

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8  Suggested reading This list is not intended to represent a complete catalogue of all relevant publications. Details of further publications can be obtained by contacting the mentioned organisations directly. IStructE publications • Appraisal of existing structures 2nd ed. (1996) (3rd ed. in preparation) • Aspects of cladding (1995) • Code of Conduct and Guidance Notes (2004) Guidance Note 3 – Checking and appraisal/review Guidance Note 4 – Surveys of residential properties • Design and construction of deep basements including cutand-cover structures (2004) • Guidance notes on the security of the outer leaf of large concrete panels of sandwich construction (1989) • Guide to inspection of underwater structures (2001) • Guide to structural use of adhesives (1999) • Introduction to the fire safety engineering of structures (2003) • Stability of buildings (1988) • Structural assessment: the role of large and full-scale testing (1997) • Structural effects of alkali-silica reaction: technical guidance on appraisal of existing structures (1992) • Structural use of glass in buildings (1999) • Subsidence of low rise buildings 2nd ed. (2000) RICS publications • Anstey, J and Powell, D. Anstey’s Boundary Disputes 3rd ed. (2004) • North, G. Anstey’s Party Walls 6th ed. (2005) • Building Surveys and Inspections of Commercial and Industrial Property 3rd ed. (2005) • Case in Point Series Building Defects (2006) Dilapidations (2006) Party Walls (2004) Negligence in Valuations and Surveys (2002) • Dickinson, P and Thornton, N. Cracking and Building Movement (2004) • Burkinshaw, R and Parrett, M. Diagnosing Damp (2003) • Rushton, T. Investigating Hazardous & Deleterious Building Materials (2006)

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• •

Redler, A. Practical Neighbour Law Handbook (2006) Hollis, M. Surveying Buildings 5th ed. (2005)

Other publications • BSI. BS 8210. Guide to building maintenance management (1986) • Carillion. Defects in buildings (1989) • CIRIA, Structural renovation of traditional buildings – R111 (1994) • HSE, Safe work in confined spaces – INDG258 (1997) • HSE, Workplace exposure limits – EH40 (2005) BRE, National House Building Council, British Geological Society, Institution of Civil Engineers and similar organisations also produce a wide range of publications which give additional guidance on matters related to inspections and surveys.

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Appendix A Survey equipment The following list of equipment does not attempt to be comprehensive but rather to act as a guide. The equipment necessary for any survey is naturally dependent on the scope and depth of investigation, as required in the brief. Those items considered particularly useful for a survey of traditionally-built medium-sized properties (commercial, industrial and domestic buildings) are highlighted by an asterisk* in the following list. General Mobile phone*, Method statement sheet, Risk assessment sheet. Tools Claw hammer*, screwdrivers*, club hammer*, floorboard saw, bolster, chisels, crowbar, jemmy, brushes, metal detector, sample bags. Recording Dictating machine*, pencil*, pen, paper*, scale rule*, tape*, camera with flash* (spare batteries), clipboard, folding rule, wax crayons/chalk, electronic measuring device. Observing Mirror*, telescope, binoculars*, torch*, endoscope (borescope). Access Collapsible ladder*, manhole keys*, demountable tower, cradle, cherry picker, scissor platform, abseiling equipment. (Note that equipment used should be certified for appropriate compliance and operatives properly trained.) Plumb and level Spirit level*, plumb line*, water level, inclinometer, precise level plus BRE levelling station system, theodolite, rotating laser. Crack measurement Crack width gauge*, suitable tell tales, vernier calipers, Demec gauge, measuring microscope. Damp Hand held dampmeter* (e.g. Protimeter), carbide moisture meter.

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Reinforcement Covermeter, potential wheels. Concrete Phenolphthalein plus spray bottle, drill and dust collection device, Schmidt hammer, BRE internal fracture test, Pundit. Soil Spade*, hand auger*, hand penetrometer, vane tester, hand sampling equipment, unconfined compression tester. Protective clothing Hard hat*, safety footwear*, high visibility vest or jacket, overalls*, life jacket (when working over water), harness (when working at height), mask, gas monitor/CO2 detector (for confined spaces), goggles, gloves.

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Appendix B  Items for possible consideration during survey work

B.1

Introduction

Structural Engineers may often be commissioned to undertake structural inspections or appraisals as outlined in Section 2.2. A well defined and agreed brief is essential so that this establishes the scope of the work to be performed. Mismatch between the client’s (particularly domestic clients’) expectations and the work carried out by the Engineer is a regular source of dispute. Engineers should therefore take steps where necessary to explain the scope of their work and any limitations that may arise to the client, and these points should be recorded. The Institution of Structural Engineers’ Code of Conduct & Guidance Notes make specific reference to Terms of reference (Note 2), Structural inspections and surveys of buildings (Note 5) and Properties in multiple occupancy (Note 6). Engineers should take steps to see that their work follows the above guidance. Engineers with the appropriate expertise and experience may be engaged on various types of survey and inspection work as described in Section 2.2. The survey might then include matters not intrinsically connected with the load bearing structure. When Engineers undertake such survey work, the standard of care in inspecting the ‘non structural’ building elements will be judged against a competent surveyor who normally undertakes such work e.g. a RICS member. Lists of possible items for consideration are given in this Appendix. The lists are illustrative and not intended to be exhaustive – they may thus include items which are not relevant in all cases. The lists should also be supplemented to cater for problems of an essentially local nature, e.g. mineral extraction, peat deposits, local records, etc. The lists have been split into those items that Engineers, subject to their brief, would normally be able to consider and items for which additional specialist advice may be required – the latter items are indicated by the shaded sections of this appendix. Before starting to examine a building in detail the following points should be borne in mind: a This list is intended as a reference for site inspection, rather than a basis for total appraisal. b Damage caused by the investigation/inspection may be a liability on the Engineer or the client where the building is owned by a third party. This may place limitations on the

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c

d

e

f

g

h

i

scope of the inspection and hence it may not be possible or desirable to examine some of the items listed. Special access and/or equipment may be required to inspect a building properly. Access may also be re­stricted because of existing use, occupancy or storage. Where lack of access limits the scope of the survey then the client should be made aware of this constraint and its implications. Engineers should try to ensure that neither their own personal safety nor that of any other person is placed at risk. Note particularly restricted and unsafe access, the possibility of noxious gases, hazardous materials such as asbestos, the presence of animals that might be dangerous, etc. If the findings of the investigation could be disputed by others then it is, where practical, beneficial to have all parties interested in the matter carry out the investigation together, e.g. such items as trial pits, examination of foundations and cutting into superstructure to examine condi­tion of hidden areas, etc. There are a number of proprietary building systems based on the use of steel frameworks, precast concrete units, timber panelling etc. These will not be dealt with individually or in detail within this list. Engineers undertaking a survey of these types of premises may use appropriate sections of this Guide, but should also be aware that in most instances of proprietary prefabricated systems specialist knowledge may be required. Some informa­tion may already be available from reference sources such as BRE. Engineers should particularly address the question of structural stability of the whole or part of the building. The possible inter-dependence of adjacent and nearby structures should be considered as well as the serviceability of the whole or part of the structural elements. The client should be advised to disclose all information on record concerning the history, use and condition of the building. The Engineer may have been told by the client, the client’s solicitors or other advisors of certain information which leads the Engineer to decide that certain part(s) of the building will not need to be inspected, e.g. certain parts of the building will be demolished, or maintenance of certain parts of the building is the responsibility of third parties. Inspection of some of the items may therefore not be relevant. If this is the case, the Engineer should make these provisos clear to the client in the report together with the rationale.

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j

Engineers would not be expected to deal with mat­ters of a legal nature, e.g. lease agreements, rights of way, etc, but might be expected to record their existence in their report. k Some clients may request preliminary cost estimates for remedial works identified during the survey. Whilst this may be undertaken by others some Engineers experienced in such matters may be prepared to offer this service. The items for consideration are grouped under the following headings: B.2.1 Preliminary considerations B.2.2 Initial inspection B.2.3 Items to ask of building owner/occupier or their representatives B.2.5 Structural concrete items B.2.6 Structural steel items B.2.7 Cast iron, wrought iron or historic members B.2.8 Timber and timber framed buildings B.2.9 Prefabricated buildings B.2.10 Retaining walls B.2.11 External elevations B.2.12 Roof external B.2.13 Metal deck sheet roofing and similar B.2.14 Internal condition B.2.15 Underfloor void B.2.16 Roof space B.2.17 External woodwork and double glazed units B.2.18 Rainwater pipes and gutters B.2.19 Drainage B.2.20 Basements B.2.21 Conservatories B.2.22 Damp ingress B.2.23 Surrounding area B.2.24 Mechanical and Electrical systems B.2.25 Modern risks B.2.26 Other areas for consideration B.2.27 Conclusions

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B.2 B.2.1

Possible items for consideration Preliminary considerations

a Check the brief and the client’s requirements. b Does the client need further explanation about the brief and the Engineer’s work? c Do the building owners/occupiers require any induction procedures to be followed (e.g. clothing, equipment, photography, etc)? d What is the extent of inspection needed? Does it include ancillary buildings (e.g. boiler houses, garages, etc)? Access arrangements. e Address of property, name and address of client. f Any other parties to whom the Engineer is responsible (e.g. funder)? g Exclusions need to be reasonable and enforceable. Is report distribution limited? Is third-party liability restricted? h Assess if the client’s interest in the property could be relevant to the appraisal, e.g. vendor/purchaser, freehold/leasehold, confidentiality. i Name of other professional advisers (e.g. selling agent). j Date and time of inspection and effect on survey. k Weather conditions at time of inspection. l Conditions of Sale, existing reports or other relevant documents. Confirm data held and provided by the client. m Do any drawings of premises exist, including modifications? Health and Safety File, etc. n Is the building listed? Any specific restrictions to the building (e.g. agricultural buildings)? o Is there a known subsidence problem in the area (e.g. highly shrinkable clay strata)? Is coal mining/salt extraction or other subterranean workings/caverns likely to affect building? p Any other known factors which affect buildings in the area (e.g. likelihood of property being on or near to filled ground (such as refuse tips), migrating gas, contaminated land registers, old railway tunnels, etc)? q Is the property situated on a flood plain or area susceptible to flooding, tidal surge or changes in groundwater levels? Old water courses. r Are there, or have there been, large trees nearby which may affect water conditions? s Outline of engineering services (e.g. ground source heat pumps, renewable energy systems at roof level, etc).

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B.2.2

Initial inspection

a Ensure your whereabouts are known to your colleagues and the occupiers of the building – consider a reporting-in system. b Walk around property, both internally and externally, to get the feel of the building and the site. c Stand back and have a good look at the building for alignment, especially roofs, chimneys, window frames, doors, etc. d Look at the surrounding buildings and area – is there a common problem (e.g. ground movement)? Common inherent faults with surrounding buildings. e What are the restrictions to the inspections? Is the building empty/occupied? Are there fitted floor coverings/heavy fixed furniture or machines? Any other restrictions on inspection? Note what you could not inspect and why. f Is the building overclad internally or externally – could it hide anything? g Any abnormal exposure problems likely – roof, cladding, etc. Does the orientation give rise to any particular problems? h What is the sub-soil? Where possible examine open ground/ garden top soil for possible indications. i Assess how you are going to gain access – safety considerations? j Are there likely to be any ‘hidden’ areas? k Is the load path reasonably clear? Does anything look as if it might be overloaded, or might have been? Any obviously ill conceived work in original construction and/or in subsequent repair/alterations? l Is it understood what gives the building its stability? m Access for maintenance. Problems?

B.2.3 Items to ask of building owner/occupier or their representatives (see also B.2.1) It is good practice to seek relevant information from the building owner/ occupier or their representative before or during the survey work. a How long has the building been in present ownership/ occupation? b Any historical information available relating to the building or surrounding area? c Knowledge of any alterations carried out, e.g. extensions, roof space conversions, wall removals, new openings, window mullions removal – conformance with Building Regulations. d Knowledge of any past major remedial works, e.g. underpinning, dry rot treatment, etc. Which parts of the building and when? Any documentation and guarantees?

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e When was the building last decorated or painted? When was the roof covering replaced? f Knowledge of any recent works carried out by neighbours or public authority (e.g. water authority). Any documentation such as party wall notice or award? g Any knowledge on previous use of the building or site? Contamination? h Have any trees or large shrubs been removed recently? Location? i If a new building, do any warranties exist (e.g. construction, professional services, equipment, etc)? Any problems with services? When last inspected/serviced? j Any building maintenance manual? Is it up to date? k Any knowledge of relevant planning notices/applications, enforcement notices, etc? l Are there any flying freeholds? Basis of allocating parking, etc. in shared property. m Any heat loss or condensation problems? n Any problems with drains? o Any problems with services or overheating to specific elevations or rooms? p Any problems with flooding? q Are roads adopted? r Any problems with access from public highway, e.g. are there rights of way or easements required/in existence? If in doubt, should a solicitor be consulted? s Do others have rights of way or access to/across property? t Are sewers/drains connected to the mains? u Are main sewers in the highway adopted? v What is the tenure of the property? w Has a risk assessment been carried out re Regulatory Reform (Fire Safety) Order? Have there been any problems regarding compliance with health and safety regulations? x Have there been any problems regarding compliance with Control of Asbestos at Work Regulations? Is there an Asbestos Register or Survey Report? y Have there been any problems regarding compliance with Occupier’s Liability Acts? z Does the building have or require an energy performance certificate? Include relevant answers in the report and/or other correspondence. Confirm all answers given where necessary. All sources of information should be attributed.

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B.2.4

Description of building

a Type of building, e.g. shed, multi-storey, detached, semidetached, terraced, etc. b Are there any lofts/attics and/or basements? Number of storeys. c Approximate age of building. Type of occupancy. d General description of materials of construction. Type of roof – slated/tiled/asphalted, etc. Type of external walls – solid/ cavity/clad/etc, thickness and bond, external rendering or weather boarding, etc. e Try and establish the principal structural arrangement, e.g. concrete frame, load-bearing brickwork, timber framed, etc. f What gives the building its stability? g Are there recognised defects of similar buildings of this era and structural arrangement? h Will there be/has there been a change of use? i Will disproportionate collapse need to be considered? (See B.2.26.1.)

B.2.5

Structural concrete items

a Identify structure type, environment and exposure conditions. b Cracking – width and pattern. • Hairline – early corrosion, shrinkage or thermal. • At beam to column connections. • In slabs at column heads – particularly top surfaces. • Spalling edges to corbels and nibs. • Overall pattern and size – overloading – structural movement. • Potential for moisture ingress. • Associated with excessive deflection. c Precast concrete. • Adequacy of bearings and tying of units. • Risk of H.A.C. – damp or humid environment, staining, deflection – do the units ring when tapped with a hammer? d Prestressed and post-tensioned systems. • Adequacy of bearing. • Condition of rebar. • Fixing into units. • Upward camber. e Other proprietary systems (e.g. wood wool formers, hollow pot floors, ‘Omnia’ planks, filler joists, etc). f Testing reports (e.g. cover, carbonation, chlorides, etc).

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g Less common issues (e.g. ASR – crazing, GRC precast concrete members, sulfate attack, FRP strengthening, etc). h Large holes/openings in slab, beams and columns – were they cast originally or cut later? i Any likely buried concrete problems? Evidence. j Sealants. k Any appreciable remedial works required – what/when? Estimate cost if requested as part of the brief.

B.2.6 Structural steel items a Define stability system • Fully framed, sway frame, braced or portalised. • Partial framing, shear walls and contribution from cladding. b Is building or any elements of it distorted? • Overall pattern of distortion. • Buckled, deflected or twisted members. Is the member acting as strut or tie? Bending. • Adequate overall and lateral stability. • Alterations or modifications. • Abnormal loading or change of use. • Sufficiency of bolt groups or missing bolts. • Quality of visible welds. Testing. • Missing components – bracing, rafter and stanchion stays, anti-sag bars and bolts. c Corrosion protection – suitability and condition of protection. Check in particular built in members, base plates, aggressive environments, etc. d Large holes/openings in slab, beams and columns – properly formed and/or trimmed. e Any evidence that the shear connectors in composite slab are not effective? f Contemporary issues (e.g. liquid metal assisted cracking, use of red lead, etc). g Suitability of bedding at bearings. Spalling/rusting at bearings. h Adequacy of secondary steelwork (e.g. plant framework, cladding support, etc). i Fire protection – any history of fire damage? Adequate. Damaged. Missing. Composite panels – rating. Building insurance requirements. j Any appreciable remedial works required – what/when? Estimate cost if requested as part of the brief.

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B.2.7

Cast iron, wrought iron or historic members

a Any evidence of eccentric loading? b What gives the member stability? Any possibility of a ‘domino collapse’ effect? c Any likelihood of vehicle impact damage? d Any loads hanging from cast iron beams? e Eccentricity of hollow cores in columns. f Any attempts at welding or other non-original fixing onto members? g Verticality of columns. h Are hollow cast iron columns used as rainwater pipes? i General state of dilapidation. j Testing – drill section or ultrasonic thickness gauge to establish wall thickness. k Built-in ends. l Any appreciable remedial works required – what/when? Estimate cost if requested as part of the brief.

B.2.8

Timber and timber framed buildings

a Any recent or historical distortion – is it significant, progressive or critical? b Connections and tying in can be unreliable (nails, dowels, brackets, flitching). Superficial filling and repair. c Critical shakes, splits, knots, etc. d Apparent solid timber surface may hide problems at depth in section – drill? e Adequacy of jointing between members. Visible? Hidden? f Check for rot/deterioration in vulnerable areas including base plates, eaves, post bottoms, joist ends, timbers built into walls, sills, water tanks, bathrooms, etc. g Examine hidden/internal cavities. Testing – permission to drill and use endoscope? h Is timber frame structurally reliant on adjacent or infill masonry walls? What is their condition? i Old buildings will probably have had many modifications – often using soft wood. Members may have been removed from the frame in past – potential instability. j Protection from permanent damp conditions – DPC. k Preservation treatment. What? When? l Age and quality of timber. m Any appreciable remedial works required – what/when? Estimate cost if requested as part of the brief.

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B.2.9 Prefabricated buildings a Age of building. Flat pack? Pod? Elemental construction? b Normally of concrete, steel or timber panels. Usually a patent type – identification of make. BRE reference. c Anything known about the make or the age of construction? d Any evidence of deterioration? • Timber – as for timber (Section B.2.8) plus check for inadequate DPCs, differential movement between timber panels and masonry cladding, bracings. • Steel – as for steel (Section B.2.6) plus check light gauge steel – local distortions, elongation of fixing holes, bearing problems. • Precast Concrete – as for reinforced concrete items (Section B.2.5) plus check for joint gasket failure, condensation, insulation, etc. e Any sign of ‘hidden construction’ – site laid masonry outside and panels inside? Tap external wall surfaces internally for possible evidence. f Are panels properly connected to each other vertically and horizontally? g Are superstructures properly fixed to foundations? Any evidence of movement? h Any signs of relevant differential movement between on site built and off site fabricated sections? i Any evidence/records of prefabrication of ‘pods’ off site? What was fabricated on site? j Temporary stability – consider eventual demolition. k Prefabricated buildings sometimes have problems in obtaining mortgage loan. l Composite panel construction – possible collapse of frame during fire. m Any appreciable remedial works required – what/when? Estimate cost if requested as part of the brief.

B.2.10 Retaining walls a b c d

Is it a ‘genuine’ retaining wall or only a facing wall? Type of construction and age. Is position critical, i.e. could failure be catastrophic? Evidence of movement, e.g. alignment, verticality, slippage, overturning, distortion, etc. e Degree of deterioration, e.g. corrosion, cracking, frost damage, chemical attack, etc. f Drainage behind and through wall. Are weep holes evident/ effective? IStructE Surveys and inspections

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g Imposed loads above wall (are they original/recent). Traffic/ overburden. Are they likely to be similar to those imposed originally, or have these changed? h Susceptibility to landslip failure. Overturning, slip circle. i Excavation or service ducts in front of wall. j Is ground in front of and/or above the wall likely to remain stable? k Any casual secondary support – propping/tying, etc? l Are the walls of a proprietary type? What is its proposed life span? m Who owns or is responsible for the wall? Is it a boundary wall? Is it shared? n Any appreciable remedial works required – what/when? Estimate cost if requested as part of the brief.

B.2.11 External elevations a Where there are cracks is their cause obvious. b Check all external walls for cracks – record crack pattern on elevational sketches. Are cracks recent or old? Size. Note proximity to trees, downpipes, gulleys, etc. c Sight along brickwork/masonry bedding, window sills, etc, for any misalignment. Also check with spirit level. Could the building have moved en bloc? d What do cracks suggest, e.g. • settlement/heave • thermal expansion/contraction • shrinkage (calcium silicate bricks) • excessive loading, etc • rusting steelwork built in • rusting cavity ties • bowing walls (possibly roof spread or cavity tie failure) • lack of tying in at floor level particularly by staircases • movement in bay windows (possibly due to installation of replacement units) • deflection of lintels. Are lintels adequate, especially bresummer beams, above bay windows or large shop openings? • corrosion of rebar in lintel, rot in timber lintels • absence of lintels (common in pre-1950s houses) • insufficient buttressing to brick arches over windows. Flattening of brick arches can cause cracks/instability and also outward deflection of return walls where these are close to the end of an arch.

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e Check walls externally and internally for plumb. Any bulging? Note bulges and check inside for movement. Could bulges have been built-in? f Is external wall moving outwards? Whole wall or just skin. Snapped headers, brickwork delamination, rubble filled wall. g Rusted brick ties/no ties. h Check round windows and other openings for excessive pointing and movement (or gaps). i Differential settlement. j Any obvious signs of major remedial works, e.g. underpinning? Does it appear to be effective? k Check verticality of corners. l Have walls adequate lateral restraint? m Any evidence of inadequate tying of walls to floors/joists, etc. n Do floors/joists span onto walls? o Are partition walls effectively built-in? p Check lintels externally and internally for excessive deflection – lintel sag cracks over windows and doors. q Check bonding and joints in brickwork, particularly the bonding of new brickwork into existing – solid to cavity. r Localised areas of repointing/cladding – may be significant. s If walls are rendered/clad, is the render/cladding cracked/ distorted or patched – if so, why? t Are stone walls badly weathered/soft? u Condition of pointing. Any pattern variations in joints? Is type of pointing appropriate? Sulfate damage to or near chimneys. v Are there clear air bricks for venting suspended ground floors? w Anything seen externally that should be checked internally, e.g. hidden areas? x Condition and stability of projecting balconies. y Comment on general standard of workmanship. z Do bay windows rely on the frames for support or are there lintel beams beneath ceilings? aa Note any pattress plates. bb Is there cavity fill or other wall insulation? Specialist survey required (e.g. thermal imaging)? cc Is there a proper DPC? Are all external ground levels sufficiently below DPC? Deterioration of materials below DPC (e.g. absorption characteristics, etc)? dd Any appreciable remedial works required – what/when? Estimate cost if requested as part of brief. IStructE Surveys and inspections

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B.2.12 Roof external a How was inspection undertaken? Ground floor level viewing, by access into roof, binocular, torch light, etc. Safety considerations may have an influence. b Consider safe working loads, fragile materials, adequate fixings for access, etc. c Are roof coverings of conventional materials? d Have the materials been changed? Heavier? Lighter – possible uplift failure concerns? e Roof tiles/slates broken, delaminated or missing. f Chimney stacks leaning. Repointing required? g Hidden valleys (horizontal gutters and potential for blockage). h Roof spread at eaves pushing out brickwork. i Roof sagging due to purlin deflection. j Slates ‘tagged’ may mean roof needs renewing soon. k Any flat roof problems likely, e.g. cold roof? Hot roof? Ventilation? Sagging? Ageing felt? Puddles? Any guarantees? l Does the roof have adequate slope to suit construction? m Chipboard, felt, asphalt, cracks, ‘bubbles’, ventilators, flashing, skirting. n Roof flashings missing around pipes and chimney stacks. o Single brick skin to roof gables/peaks. p Are bonnet and valley tiles properly nailed/pegged to battens? q Adequate support to services crossing flat roofs. r Excessive moss growth on roofing. s Adequate ventilation – eaves/ridge vents or air bricks? t Sunlight deterioration. Solar protection paint, chippings, etc. u Any GRP architectural features? v Any appreciable remedial works required – what/when? Estimate cost if requested as part of the brief.

B.2.13 Metal deck sheet roofing and similar a Type of material (e.g. asbestos cement, profiled metal decking, etc). Manufacturers´ details. b Access/safety (e.g. lichen, moss, wet surfaces, fragility, roof lights, etc). c Is it brittle? Cracked/damaged sheets. Repairs. d Angle of roof. Does it require sealing? e Purlins sagging/twisted or insufficient. f Washer tightness and effectiveness. g Vulnerability to excessive snow loading. Particularly in

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h i j k l m n o p q r s t u v

locations where there can be accumulation of snow (e.g. adjacent to tall buildings, valleys, etc). Insulation boarding/lining sheets sagging. Rusting fixing bolts/caps – check tightness. Translucent sheets/roof lights – cracks, insulation. Water penetration to edges, fragile. Perimeter barge boards – overlaps/fixings. Adequacy of flashings around service penetrations through roof. Steel sheets – rusting at ends/rust patches. Buckling and distortion. P.K. screws or through bolts. Protection. PVF2/PVDF, Plastisol, Polyurethane, Powder coating, Polyester. Colour fastness, chips, scratches, warranty, rust. Aluminium – contact with other metals, mill finish. Adequacy of gutters and downpipes – overflows, weirs, blocked, internal. Durability of surface paint, plastic covering, bitumastic, galvanising, edge corrosion, etc. Are laps in sheeting away from prevailing winds? Any exposure problems? Adequacy of insulation. Condensation lines may show insulation inadequacy. Does sheeting contain asbestos – what type? Any appreciable remedial works required – what/when? Estimate cost if requested as part of the brief.

B.2.14 Internal condition a Plan your inspection logically so as not to get lost/confused – watch access, safety, etc. b Suggest draw small sketch plan of each floor level and mark on crack patterns – particularly ceiling cracks – relevance. c Anything seen outside which should be checked inside (e.g. bulges, cracks, etc). d Movement of upper floor skirting relative to floorboards (wall not tied back to floor). e Lateral load onto walls at eaves level (e.g. skeiling at top floor/ raised ceiling joists, etc). f Internal cracking not corresponding to external (e.g. drying shrinkage of concrete blocks). g Cracks around junction of external walls and party walls. Are the walls properly bonded? h Cracks due to timber levelling plates in brick walls. i Differential movement between spine wall and other walls (different depth and size of foundation). IStructE Surveys and inspections

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j k

l m n o p q

r s

t u v w

x

y

z aa bb cc dd

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Defects due to previous water leaks (e.g. below water tanks, bathrooms, washing machines). Examine each room/area. Cracks in cornices, walls and ceilings. Any hollow or bulging plaster? Any recent decoration/ cladding – could it hide something? Any sloping or sagging floors/beams – relevance? What is construction? Ground bearing concrete floor slabs – sulfate attack, settlement. Any bumps or hollows? Look around edges of skirting. Direction of joists/floors span. Floor joists/wall plates built into outside solid walls – rot. Are all upper floors and walls properly supported by beams or walls below? Are there upper walls above lower walls? In houses/flats check hallways and through lounges. Solid floors – gaps under skirting may suggest settlement. Has any original structure been removed/modified? Building Regulations approval. Is everything properly supported (e.g. walls, chimney breasts, etc). Unevenness of walls. Possible plastering over of defects. Examine window frames and sills – any rot/filling? Can they be opened? If not, why not? Movement in bay windows. Square or jamming of doors and windows – settlement, heave, racking, deflection. Also binding of doors and windows. Are walls solid, cavity, timber panel, studwork, lined? Brick infill within timber stud wall. Check outer walls for lining – could indicate damp problems or timber frame. Panelling against outside walls can disguise rot, particularly in basements. Also kitchens, canteens, bathrooms, and other ‘damp’ areas. Cavity wall tie bridging problems. Use dampmeter – especially at ground floor level (debris filling the cavity to above the level of the DPC). Dampness in ceilings/chimney breasts due to defective flashings or soakers. Look above false and suspended ceilings if possible to examine building structure. Has there been a loft conversion? Adequate upgrading of joists. Alternative support for purlins. Building Regulations approval. Patio door ventilators. Window sizes relative to room sizes. Window safety glass. Building Regulations. Skirting boards – movement at ends (filling) and gaps underneath.

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ee Any ‘crinkled’ timber surfaces? Investigate with probe? Evidence of rot? ff Any open joints in doors/windows? Recent installation of heating system can cause timber and ceiling materials to shrink and crack. gg Woodworm – staircases, bay windows particularly, also back of furniture and under floor coverings – is it active? hh Any rusted or rotted window frames? ii Means of escape – windows/stair. Building Regulations implications. jj Test ground bearing slabs for damp penetration. DPC below slab. Mould beneath floor coverings. Any damp penetration through joints of PVC floor tiles? kk Damp spots on walls/ceilings. Leaking roof. Leaking rainwater pipes. Bad external pointing to solid walls. ll Fractured DPC. No DPC. mm Any appreciable remedial works required – what/when? Estimate cost if requested as part of the brief.

B.2.15 Underfloor void a Be aware of personal safety in confined areas (e.g. height restrictions, lack of breathable air, wasps’ nests, etc). b Comment on the general standard and condition of the void. c All joists/spans properly supported. d Any notched joists, e.g. for services, etc? e Ends of joists above D.P.C. – sound? – probe? f Any evidence as to possible depth of foundations below void level? g Are any areas of void inaccessible? Any solid floor areas? h Any deterioration of R.C. work, e.g. spoiling cover, rusting bars, etc. Any deterioration of steel members – check supports? i Is there any oversite concrete? j Any wet or damp areas on void surfaces – why? k Any pointing/rebuilding required to brickwork? l Air bricks effective and with adequate through ventilation. m Any soil gases, e.g. methane, radon, carbon dioxide, etc? n General state, support and tidiness of wiring and other services items. Any notched joists? o Any timber rot (dry or wet)? Any evidence of replacement timberwork or of other floor deterioration? Is source of defect now removed? p Any heating systems that may dry out the substratum. q Any appreciable remedial works required – what/when? Estimate cost if requested as part of the brief. IStructE Surveys and inspections

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B.2.16 Roof space a Is there access to all areas? Is it safe? Footing. Should access be made into any ‘hidden areas’? Advise client. b Did any external evidence suggest possible internal problems, e.g. flashings, sagging, etc? c Is there any excessive storage loading? d Are tiles/slates back pointed or have they sarking felt beneath battens? e Verticality of trussed rafters. Triangulation. f Are timbers sound – dry or wet rot, any damp patches, splits or woodworm? g Are steel/R.C. members sound – no spalling/rusting? h Are roof trusses sound, e.g. joints, bracing, straps, etc? General stability. i Are rafters, purlins, ceiling joists or binders significantly deformed or undersized? j Are rafters or purlins adequately supported? Any rot at ends of timber purlins on walls? k Are there sufficient angled timber struts to support purlins? Do the struts bear onto load bearing elements below? l Was ‘strengthening’ retrospective and was it carried out properly? m Are ends of inclined rafters adequately tied across or into building? n Are rafters and purlin connections sound? Have timber trusses proper plate/bolt connections and adequate protection (galvanising)? No missing, broken or ‘adapted’ members. o Is brickwork sound? Is it sufficiently tied to the roof structure? p Are corbel brick supports for purlins or upper wall plate sound? q Has wall plate moved off brick supports? r If chimney breasts below have been removed, does remaining upper section rest on ceiling joists or is there proper support? s Has there been a loft conversion? Adequate upgrading of joists. Alternative support for purlins. Building Regulations. t Is insulation present? Suitable? Adequate? u Is roof space properly compartmentalised (e.g. full height party walls)? v Do birds/animals have access – any evidence? Wasp nests? w General standard and condition of areas – is it ventilated? Pipework? Wiring? Asbestos? x Any appreciable remedial works required – what/when? Estimate cost if requested as part of the brief.

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B.2.17 External woodwork and double glazed units a Comment on the general standard of external timberwork and its maintenance. b Check doors and window frames for out of plumb and out of square. c Investigate with blunt probe at a few joints in door and windows to see if they are soft or ‘filled’ – be aware of responsibility for damage. d Check joints to ensure they are not open to allow rain penetration. e Look at bottoms of posts and ends of built-in members for rot and movement. f Are there signs to suggest that a specialist timber survey is required? Treat recommendations from such surveys objectively particularly those in so-called ‘free’ surveys. g Will any significant amount of external timberwork/cladding be likely to require replacing or significant maintenance in the near future – 1 year? 5 years? h Are double glazed units performing any structural function (e.g. mullions to bay windows, etc)? i Anything seen externally that requires checking internally? j Are windows, etc; timber, metal or PVC? k Are all external timber members adequately protected from rot? Properly primed and painted? Window putty sound – correct type? l Are timber items weathered (e.g. drips)? m Could recent repainting hide deterioration (e.g. fascias, soffits, etc)? n Are double glazed units free of internal condensation? o Are double glazed units secure from bead removal? p Workmanship/dilapidation/repairs. q Any appreciable remedial works required – what/when? Estimate cost if requested as part of the brief.

B.2.18 Rainwater pipes and gutters a What are they made of (cast iron/PVC/concrete/fibre cement)? b What is their condition? Leaks and rusting at rear of cast iron work and concrete gutters. c Any ‘green’ patches on walls or other evidence indicating leaks/blockages/overflowing? d Any pointing locally eroded or cladding stained? e Any evidence of back falls on gutters? Are gullies clear? Fixings of pipes and gutters and stop ends of gutters.

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f g h i j k l m

Where appropriate, are gutters and pipes protected from corrosion? Check internal surfaces of gutters. Any gaps between edge of roof and gutters? Any local frost damage to walls indicating possible leaks? Any RWP inside building or within structure? Problems? Are trees/climbing plants likely to cause problems? Is there a rainwater or greywater collection system above/ below ground storage function? Any appreciable remedial works required – what/when? Estimate cost if requested as part of the brief.

B.2.19 Drainage a Is it attached to mains system or septic tank? Building Regulations? Are there soakaways? Where? Is it a combined or separate system? b Are there manholes and gullies to facilitate maintenance? c Can you lift any manhole covers? • Condition/depth/flow, etc. • Are pipes clear? • Are pipes shallow? d Any exposed drains running inside buildings? Could leaks have serious consequences? e Are manholes inside buildings double sealed? f Do you know which manholes serve the various sinks, lavatories, etc? g Any internal rainwater pipes? h Is clearing of manholes and rodding of drains convenient? Will internal access to building be necessary? i Any trees or large bushes nearby? Root damage? j Any known problems? Ask and record replies. Is system shared with neighbours? k Any obvious foul system leaks? Any health risks? l Who owns the drains? Note that pre 1936 drains which serve two or more properties are S24 sewers under the Public Health Act 1936. m Do any drains not serving the property flow into the system on the site? Responsibilities? n Is attenuation provided on the site, is there a SUDS system? o Any appreciable remedial works required – what/when? Estimate cost if requested as part of the brief.

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B.2.20 Basements a Adequate ventilation. Heating plant, wood moisture content, etc. b Any modifications? Dry lining. c Tanking (guarantees). d Water seepage. e Lining – type/how/when? f Deterioration of load bearing members (e.g. wall mortar, spalling bricks, etc). g ‘False’ walls/floors. h Sumps/non-return valves/pumps (inside/outside). i Underdrawn ceilings – anything hidden? Preventing air circulation. j Can you see beam/joist seatings (rot/corrosion)? k Corrosion in filler joist floor particularly around old pavement lights in public houses. l Walls bulging – lateral adequacy. m Heating plant drying out substratum. n Presence of damp/rot/deterioration. o Retaining wall effects (see also B.2.10). p Floors ‘humping’. q Access to other areas – sub-floor voids. r Part basements. s Any evidence of bridging to damp proof course? t Any appreciable remedial works required – what/when? Estimate cost if requested as part of the brief.

B.2.21 Conservatories a Material selection. Protective coatings as appropriate. b Loadings. Snow: drifting, sliding from higher roofs. Wind. Minimum imposed. c Load paths and overall stability. Holding down. d Lateral stability, wind posts, connections to foundations, dwarf walls, knee joints at eaves – distortions. e Tension members, fixings/connection. f Compression members, bracing across lanterns. g Support of box gutters, cantilever brackets, fixing and flashing to walls. h Foundations, resistance to uplift. i Deflection effects on glass. Maximum glass sizes. Failure of double glazing. j Polycarbonate roofs – noise.

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B.2.22 Damp ingress a Ground level – skirting and walls. b Ground level – floor timbers positioned near walls – external walls. c Door piers. d Solid walls (poor pointing and perished bricks). e Chimney breast below upstairs ceiling levels. f Damp patches on roof timbers (where accessible) – may be old. g Unused chimney breasts – ventilated. h Path overlays – above DPC. i Limitations/effectiveness of injection DPCs. j Any appreciable remedial works required – what/when? Estimate cost if requested as part of the brief.

B.2.23 Surrounding area a Condition of roadways, parking areas, paths, drives, etc. – localised settlement. Drainage problems. b Any trees or shrubs likely to cause problems? Proximity. Roots. c Condition of detached sheds, garages, etc. Asbestos roofs. d Free standing walls – condition, stability, etc. e Any significant changes in level or retaining wall issues? (See also B.2.10.) f Any site activities that can cause contamination? g Are boundaries clear and established? Condition. h Condition and ownership of boundary walls, fences etc. i Are roads adopted – street lighting/drainage? Is it necessary to check with the Local Authority? j Could water flood to property from any adjoining roads/land? k Any rights of way apparent e.g. gates in hedges or fences or tracks in the ground? l Any public utilities known to be crossing the site which do not serve the property? Who will check? m Any appreciable remedial works required – what/when? Estimate cost if requested as part of the brief.

B.2.24 Mechanical and electrical systems B.2.24.1 General a If unable or insufficiently experienced to check services, make this clear to the client. b Building management systems. IT controls. When last updated/ replaced?

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c If acting for purchaser when fixtures and fittings are to remain – solicitor to check. d General standard of fixtures and fittings, e.g. offices, bathrooms/toilets, kitchens, canteens – try everything to see if it works. e Which services are laid on and connected (gas, water, electric, telephone)? f Evidence of leakage and signs of potential problems? g Availability of maintenance/service records, O&M manuals and building log books. h Adaptability of systems. i Evidence of asbestos associated with services. j Any renewable energy systems installed (e.g. wind power, photovoltaic, solar thermal hot water, biomass boiler, combined heat and power)? k Any appreciable remedial works required – what/when? Estimate cost if requested as part of the brief. B.2.24.2 Water and sanitary ware a Correct isolation valve and drain at point of entry. b Buried to correct depth. c Insulated to prevent freezing and/or heat loss. d Age, condition and type of pipework. e Metering arrangement (if present). f Legionella compliance. g Water supply regulations compliance. h Adequate pressure and flow. i Evidence of water hammer. j Condition of sanitary appliances. k Condition, size and accessibility of water storage tanks. Condition of insulation to water storage tanks. B.2.24.3 Gas a Correct isolation valve at entry. b Entering pipework installed to minimise risk of damage from structure. c Adequate ventilation to meter and enclosed voids. d Adequate ventilation for appliances. e Pipework type and fittings. f Gas pressure. g Compliance with gas safety regulations. h Correct labelling. i Gas pipework schematic fitted adjacent to meter. j Gas isolation system to kitchen cooking/canopy. IStructE Surveys and inspections

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B.2.24.4 Heating a Type of heating. b Controls. c Age and condition. d Appliance details. e Adequacy of system size. f Standard of insulation. g Feed and expansion arrangements, including safety valves. h Flue arrangements. B.2.24.5 Ventilation, air-conditioning and comfort cooling a Legionella compliance (specific attention to sprayed water humidifiers and water cooled chillers). b Type and future availability of refrigerants. c Cleanliness of system. d Age and condition of systems. e Provision of fire dampers and fire protection. f Access doors. g Adequate insulation. h Air-conditioning Inspection Report (may be a requirement from January 2009 for systems of more than 250kW and January 2011 for more than 12kW of cooling). B.2.24.6 Electric, power and lighting a Metering and isolation at point of entry. b Main equipotential bonding arrangement (including earthing/ grounding) and lightning protection. c Supplementary bonding. d Protective devices. e Age/condition of accessories and fittings. f Type of wiring and arrangements of circuits. Fixed electrical wiring tests. g Adequacy, age and condition of general luminaries. h Adequacy, age and condition of emergency luminaries. i Deviation from BS 7671 (IEE wiring regulations). j Fire alarm coverage, standard and condition. k IT, data and telecom provision and condition. l Provision of other ancillary services. m Mega-testing of circuits for deterioration of insulation. n Ownership of transformer/sub-station and 24 hour highway access available.

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B.2.24.7 Energy efficiency a Heat recovery. b Adequacy of controls. c Energy efficient appliances and lighting. d Solar control. e Standard of insulation. f Zoning and interaction of systems. g Excessive plant sizes. h Energy surveys available. i Has the building a Building Management System? When was this last calibrated and checked? j Other building services issues. • Existence of ground source heat pumps which may cause frost heave adjacent to buildings. • Existence of roof mounted renewable energy systems (e.g. wind, power, solar thermal water heating, photovoltaic) – adequacy of support, etc. • Presence of biomass boilers? Is the fuel supply secure and available? • Has a thermal model been constructed and Building Regulation approval obtained under Part L with respect to overheating and carbon dioxide emission controls?

B.2.25 Modern risks a Have you considered topics that are currently thought to be ‘modern risks’? Examples are: • Polystyrene: e.g. ceiling tiles, insulation behind wallpaper, roof insulation, etc. • Asbestos: Anything noticed during survey (e.g. pipes lagging, flues, roof tiles, gutters, artex ceiling finishes, AIB/Asbestolux boards, etc)? Does the asbestos present an imminent health hazard? Could it do so in the future – why and how? Is it reasonable to recommend a specialist survey? • Toxic mould: Any mould noticed? Can you classify it? What is the latest authoritative thinking on the subject? • E-smog: Is the property situated close to transmission lines, tower or masts? How close? What is the latest authoritative thinking on the subject? • Contaminated land: Is the property likely to have been constructed on a site that may have contamination below it? Can you check? Dangerous gas from below or adjacent site?

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• Radon: Reference to be made to Indicative atlas of radon in England and Wales HPA-RPD-033 (2007) for areas of severity. Is there oversite concrete or membrane below subfloor voids? Are services entries sealed? Is there sub-floor ventilation? Is there cavity ventilation and is the dampproof course connected to a gas-proof membrane? b Do you cover these items or exclude them? Is it reasonable to exclude dealing with them? To what extent is it reasonable to deal with them?

B.2.26 Other areas for consideration B.2.26.1 Building Regulations 2000 The Approved Document to Part A of the Building Regulations in England and Wales was revised in 2004. The provisions needed to satisfy Requirement A3 on disproportionate collapse have changed significantly. The previous governing criteria of 5 storeys or higher was removed, and replaced by a system of Building Classes determined by building type and occupancy. Where new storeys are added to an existing building, or where there is a change of use, the building may need to satisfy the current Building Regulations. This could mean the introduction of new horizontal and/or vertical ties and other structural works. a Does the proposal require the building to satisfy the current Building Regulations with regards to A3 disproportionate collapse? b Has there been any discussion with building control on their views or likely requirements? Other parts of the Approved Documents have also been revised e.g. Parts F, L and N which could also have implications. B.2.26.2 Defective Premises Act 1972 The Act requires new dwellings to be ‘fit for habitation’ when completed. The Act applies to situations when existing nondomestic buildings e.g. agricultural buildings, warehouses are converted into new dwellings for the first time. The governing criterion for the Engineer to consider is ‘fitness for habitation’ – a strict obligation rather than to exercise reasonable skill and care. a Is there a change of existing building use to provide new dwellings? b Are the existing building elements e.g. foundation sufficient to see that the new dwelling will be ‘fit for habitation’ c If defects are found in such new dwellings, do the defects render the dwelling not ‘fit for habitation’?

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B.2.26.3 Party Wall Act 1996 The Party Wall Act 1996, currently applicable in England and Wales, requires the Building Owner to notify the Adjoining Owner(s) if they wish to carry out certain works to the Party Wall and/or excavate close to the boundary between the parties. There is a set prescribed procedure within the Act which should be followed. Failure to follow the procedure could mean delays (injunctions) or damages (civil claims). The Engineer should carefully consider the Act and advise the client of the works which are within its jurisdiction, e.g. removal of chimney stacks, cutting pockets into the wall such as for padstones, raising the wall, underpinning, any excavation work within 3m or 6m of the party wall or the adjoining owner’s wall foundation which is likely to be below the level of the existing foundations (see Sections 2 and 6 of the Act). a Check building ownership – where is the party wall and the site boundary? In flats, there could be party structure (floor dividing the flats). b Is there/has there been works to the Party Wall or close to the building boundary within the jurisdiction of the Party Wall Act? c Has the Party Wall procedure been followed correctly by the Building Owner and the Adjoining Owner? d If defects are found, are they likely to be the result of the works? A Party Wall Surveyor should be consulted if the Engineer is not sufficiently experienced in Party Wall work. B.2.26.4 Disability Discrimination Acts 1995 and 2005 Part of the aim of DDA is to allow access for all to everyday services e.g. council buildings, doctor’s surgeries, hotels, banks, pubs, places of worship, etc. Service providers are required to make ‘reasonable adjustments’ to the way they deliver their service (including their premises) so that people with issues of mobility can use them. What is accepted as ‘reasonable adjustments’ will differ depending on the resources of the provider; for example the Act does not insist on adjustments to ecclesiastical buildings of historic and architectural importance. a Is DDA applicable to the building being surveyed? b Is structural work such as ramps, lifts, larger openings for wheel chair access likely to be necessary for the building?

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A full DDA survey by a qualified specialist surveyor is usually the recommended route to see that the service provider becomes DDA compliant. The specialist surveyor will look at how the service is provided as a whole to satisfy DDA requirements, rather than just the physical premises which the Engineer will normally focus on.

B.2.27 Conclusions a The conclusions may provide a general view of the state of the property e.g. good, medium or poor. The conclusions could then show, probably by exception, what the major points of concern were. b Care should be taken before arriving at definitive conclusions, particularly with regard to the likelihood of future deterioration or progressive movement. c If unable to inspect or gain access to certain areas, this should be explained to the client. d Any specialist opinion required – timber survey, electrical survey, central heating survey, etc? e Consider age of building, type and location, and possibly problems arising in the near future, e.g. wall tie failure, roof covering failure, height of nearby trees, etc. f Is there evidence, or does the owner know of any structural alterations since original and does this work have Building Regulations approval and/or planning permission? g Are any additional structural members required? Stability, excessive loads, structural movement? h Building being used for its original purpose. Loading implications. i General impression of degree of maintenance. j Put a budget price on the remedial work only if requested in the brief and give an assessment of how urgent it is. k Is any work required immediately, e.g. for safety reasons? l Is it necessary to make any enquiries from the Local Authority regarding any known future planning intentions, development, etc? m Have the areas of uncertainties/limitations of the survey been adequately explained/discussed with the client? n Go outside and have an overall look from a distance. Have you had sufficient time to answer your brief properly? Why not? o HAVE YOU ANSWERED YOUR BRIEF?

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The Institution of Structural Engineers International HQ 11 Upper Belgrave Street London SW1X 8BH United Kingdom T: +44 (0) 20 7235 4535 F: +44 (0) 20 7235 4294 E: [email protected] W: www.istructe.org

Guide to surveys and inspections

This Guide is for the benefit of Engineers and Surveyors already familiar with inspecting, appraising and reporting upon buildings and associated structures. It is an update of the popular Guide to surveys and inspections of buildings and similar structures and provides guidance on the overall methods to the approach and reporting of inspections, including the safety and legal considerations surrounding them. Moreover, extensive checklists are provided to give on-site support whilst carrying out an inspection. The document is a succinct and handy pocket-sized guide for use before and on-site during an inspection/ survey; it is ring bound for ease of use and printed on durable, water-resistant paper.

IStructE

Guide to surveys and inspections of buildings and associated structures

Guide to

Surveys and inspections of buildings and associated structures June 2008