Building standards technical handbook 2020: domestic

The Building (Scotland) Act 2003 gives Scottish Ministers the power to make building regulations to:

This document gives guidance on how to comply with these regulations.

This is one of two Technical Handbooks, one covering domestic buildings and the other non-domestic buildings. These Technical Handbooks have been issued by Scottish Ministers for the purpose of providing practical guidance with respect to the requirements of the provisions of the building regulations under a notice given in accordance with Section 4(2) of the Building (Scotland) Act 2003. Each Handbook has eight sections. Section 0, this section, is identical in both Handbooks. It covers general issues and sets out how and when the regulations apply to buildings and works.

From the 2013 edition onwards, the Handbooks are published electronically and are available free on the Scottish Government, Building Standards Division website.

Sections 1 to 7 give guidance on how to achieve the standards set by the regulations, and there are different sets for domestic buildings and non-domestic buildings. The seven sections each cover a number of related standards. They are:

Section 1 Structure

Section 2 Fire

Section 3 Environment

Section 4 Safety

Section 5 Noise

Section 6 Energy

Section 7 Sustainability

Each of the seven sections consists of an introduction and then general guidance on the standards within the section. This is followed be each standard which has specific introductory information and guidance on how to comply with the standard. At the of the Handbook, after Section 7, there are the following two sections:

Appendix A: Defined terms.

Appendix B: List of standards and other publications.

The Technical Handbooks are supported by a Procedural Handbook, published separately, which clarifies the intent of the Building (Scotland) Procedures Regulations 2004. A separate procedural guidance document for Crown buildings has also been produced.

This Technical Handbook gives guidance on achieving the standards set in the Building (Scotland) Regulations. The standards themselves can be found in schedule 5 to regulation 9, and are in the form of ‘expanded functional standards’. That is, the standards describe the functions a building should perform, such as ‘providing resistance to the spread of fire’.

The Building (Scotland) Regulations made by the Scottish Ministers are subject to approval by the Scottish Parliament. The content of the regulations, so far as it relates to technical specifications, is also scrutinised by the European Commission (EC). The EC checks with all the other countries that have adopted the Construction Products Regulations (CPR) to ensure that no barriers to trade in construction products are created, either directly or indirectly by the way products are described.

To meet the requirements of the CPR, materials and construction methods must be described by use of suitable European Standards wherever these exist. As there is a rolling programme of change to these National and European Standards, which includes conversion to, and the further provision of, ENs and harmonised ENs, the Handbooks have been designed to be readily updated. An explanation of the relevance and status of specific European and British standards referred to in the Handbooks is in the section concerned. There is also a list of the publications referred to in the Handbooks provided in Appendix B.

The arrangement of Sections 1 - 7 within the Handbooks relates directly to the Basic Works Requirements of the CPR (as published by the EC), which construction works are expected to satisfy when they have been properly designed and built. The arrangement is as follows:

Section 1 Structure (EC - Mechanical resistance and stability)

Section 2 Fire (EC - Safety in case of fire)

Section 3 Environment (EC - Hygiene, health and the environment)

Section 4 Safety (EC - Safety and accessibility in use)

Section 5 Noise (EC - Protection against noise)

Section 6 Energy (EC - Energy, economy and heat retention)

Section 7 Sustainability (EC - Sustainable use of natural resources)

The building regulations are enforced through the building standards system that is established by the Building (Scotland) Act 2003. The Act sets out the enabling powers that allow Scottish Ministers to make, not only the building regulations, but also procedural regulations, fees regulations and the other supporting legislation needed to operate the system. The system is designed to ensure that new buildings and works achieve the objectives of the Act in terms of health, safety, welfare, convenience, conservation of fuel and power, and sustainable development.

The roles of those operating the building standards system are explained in detail in the guidance on the procedural regulations. Briefly, the duty to comply with the building regulations lies with the owner, or in some cases the client, for the work. Before work begins a building warrant must be obtained.

For some simpler works a warrant is not required (see regulation 5 and schedule 3), but the regulations still apply. The owner or client again has the duty to comply. The role of issuing warrants and accepting completion certificates rests with verifiers, enforcement is by local authorities, and the system is overseen and updated by the Building Standards Division (BSD). BSD forms part of the Scottish Government and acts on behalf of, and is responsible to, Scottish Ministers. These bodies are further explained in the guidance to the procedural regulations.

The building standards system is pre-emptive, ensuring so far as possible that the proposed works will comply with the regulations. It recognises that proposals can change during construction, so there are requirements for amendments to the proposals to be agreed and recorded. On completion, the owner or client must certify that the works have been constructed in accordance with the building warrant and the building regulations. The verifier will make reasonable inquiry to ensure the completion certificate is accurate before accepting the certificate. Usually an inspection of the works will be made, and on most projects some inspection of work in progress will also have been carried out. However verifiers cannot inspect all materials and work on every building site. It is the client that should put in place the contractual and practical arrangements needed to assure themselves that the desired quality of work has been achieved.

The regulations are mandatory, but the choice of how to comply lies with the building owner. This Technical Handbook has been issued by Scottish Ministers, through the Building Standards Division, for the purpose of providing practical guidance with respect to the building regulations. If the guidance is followed in full then this should be accepted by the verifier as indicating that the building regulations have been complied with. However it is quite acceptable to use alternative methods of compliance provided they fully satisfy the regulations.

Failure to comply with the Technical Handbook does not render a person liable to civil or criminal procedures, but proof of compliance with the guidance may be relied on in any proceedings as tending to negative liability for an alleged contravention of the building regulations.

Following the advice in the Technical Handbooks is therefore likely to be the normal way of complying with the building regulations. However, a designer may put forward other ways of meeting the regulations, in the form of alternative solutions.

There are a further three guidance documents that have the same standing as the Technical Handbooks. Scottish Ministers have issued these under Section 4(1) of the Building (Scotland) Act 2003. These are:

In due course other documents may be issued by Scottish Ministers to provide further guidance. Such guidance might deal with specific building types, or provide alternative methods of showing compliance with those provided in the Technical Handbooks.

The use of expanded functional standards, backed up by detailed guidance, provides a flexible system of control. Consideration of alternative solutions is assisted by the expansion of the functional standards previously used in the building standards regulations to clarify the necessary properties of each building. The need for a formal relaxation of standards is reduced as meeting the full details of given solutions is no longer mandatory. The professional judgement of the verifier, assisted by guidance on questions referred to Scottish Ministers, through the Building Standards Division, decides whether a standard is met.

In considering alternative solutions, however it is necessary to have regard to the details of this guidance. Where performance standards or policy statements are given, every part of the solution is expected to meet them. As a result, alternative solutions that appear suitable may not be acceptable in detail. For example, some of the solutions offered in relation to the English and Welsh building regulations, in the ‘Approved Documents’ (ADs), are not suitable because the levels of thermal insulation recommended are not the same. Similarly different approaches are taken to the control of fire size and the design of compartmentation which means that constructions meeting the AD on fire safety may not be acceptable. This will vary in time as both ADs and the Scottish Technical Handbooks are updated. Solutions based on other documents, such as British or European Standards, will have to be carefully evaluated to see if the Scottish standards are being met in an appropriate manner.

Where any building contains both domestic uses and non-domestic uses, the appropriate parts from each Technical Handbook will need to be used to ensure the standards are complied with in full, for example a caretakers flat in an office building. However, communal rooms or other areas in a block of dwellings that are exclusively associated with the dwellings should be considered using the domestic guidance. Examples of this might be a room used as an office for the operation of a sheltered housing complex or a lounge communal to a block of dwellings. It is also a general principle that where a building or part of a building might be seen as falling into more than one category it should be designed to meet the most stringent recommendations.

The following is a summary of the changes which have been introduced since 1 May 2011. Very minor changes to text have not been included here.

It is intended that this Technical Handbook will be available in electronic form and available free of charge on the Building Standards Division website http://www.scotland.gov.uk/topics/built-environment/building/building-standards/. It is not expected that the standards will change regularly as these are set in the building regulations and can only be changed with Parliamentary approval. Therefore it is anticipated that the guidance will be replaced more regularly than the standards themselves.

Section 0 is arranged to follow the actual regulations. This sub-section provides an introduction to the building standards system. Sub-section 0.2 covers regulations 1 and 2 which are the citation, commencement and interpretation. Sub-sections 0.3 to 0.15 cover the significant technical regulations with each sub-section setting out and discussing the regulation with the same number (sub-section 0.3 covering regulation 3 etc.). Regulation 16 establishes which regulations cannot ever be relaxed by Scottish Ministers. These are the regulations on citation and commencement, interpretation, exempted buildings, work not requiring a warrant and the methods of measurement. Regulation 17 was introduced in 2007 to help with the implementation of the Energy Performance of Buildings Directive.

Scottish Ministers can, under Section 7 of the Building (Scotland) Act 2003, approve schemes for the certification of design or construction for compliance with the mandatory functional standards. Such schemes are approved on the basis that the procedures adopted by the scheme will take account of the need to co-ordinate the work of various designers and specialist contractors. Individuals approved to provide certification services under the scheme are assessed to ensure that they have the qualifications, skills and experience required to certify compliance for the work covered by the scope of the scheme. Checking procedures adopted by Approved Certifiers will deliver design or installation reliability in accordance with legislation.