Building Control guidance notes

This note is intended to give guidance on the format and extent of information that needs to be submitted in support of Building Regulations applications.  This is to enable us to assess your submissions more effectively, and to give a more targeted and efficient response.

We are more than happy to discuss your proposals prior to the Building Regulations Application being made. Therefore if you have any queries or would like to discuss your scheme please contact us.

This information does not have to be submitted at the time of the application

This is because Structural information is normally required in response to conditions that we attach to an approval. Therefore structural calculations and drawings can be submitted when the design is sufficiently developed. However, you should ensure that this is submitted in advance of the works commencing to reduce the potential risk of abortive work. This is particularly relevant to piling design and innovative design solutions.

What sort of information do we need to assess your proposals?

You should submit a design summary with every submission which contains the following:

1. a list of the structural design codes with which it complies;
2. an explanation of the basis of design.  This requires sufficient detail to allow others to understand the structural principles used;
3. the class of the building for purposes of disproportionate collapse design (Table 11 of Approved Document A).  If the building is in a number of classes, describe the division;
4. description of the measures taken to guard against progressive collapse;
5. description of the load-path to the foundations and how lateral stability is achieved (with illustrations as required to give sufficient clarity);
6. name of the organisation, or individual, who has overall responsibility for the stability of the structure as required by the design codes;
7. a schedule of the software used, and for what purpose; confirm that its application and limitations are understood and that the results have been verified; and
8. a statement of the qualifications of the person undertaking the design, whether the design has been subject to any in-house or third party checking, and the name and qualifications of the person doing that checking.

The design should then be submitted, in a clear and readable format, with clearly referenced pages. Elements should be consistently referenced and highlighted on plans. Design submissions are not necessarily required for all elements, but you should include the design for typical elements, all transfer structures, unusual and safety-critical elements. Foundation design and assessment of any effects on existing structure should also be submitted. Supporting documentation, such as results of any site investigation or tests should also be included.

This note is intended to give guidance on the acceptability of Structural designs using Eurocodes.

Since 2002, a series of Structural Design Codes ‘Eurocodes’ (BSEN 1990 – 1999) have been progressively published. The structural Eurocodes are a set of standardised European design standards which provide a common approach to structural design across the EU.

On 31 March 2010, BSI withdrew all conflicting standards.The City of London District Surveyors Office has a member on the Institution of Structural Engineers’ Standing Committee on the Implementation of Structural Eurocodes, and so has been at the forefront of developments in this area.

When Approved Document A was revised in October 2013, Eurocodes were referenced by the Secretary of State as guidance on meeting the requirements.

Approach of City of London Building Control

On 29 January 2010, The Department of Communities and Local Government issued guidance to all Building Control Bodies which made clear the approach to be adopted.

All designs are judged on their merits, there is no requirement to design to any particular code. When assessing designs we will take account of the suitability of the code of practice being designed to. Older codes which are not maintained are less likely to reflect current design practices, and issues which have subsequently been found to be a problem will not have been incorporated. Therefore, if you wish to use any design standard other than the Eurocodes, you should justify its application. The recently withdrawn British Standards are likely to remain safe for use for some time, and designs will be looked upon favourably. However the City of London District Surveyor's Office cannot support users who use a combination of the Eurocodes and withdrawn British Standards in their design without appropriate justification.

Matters to consider

You need to be aware of the risk of inappropriately mixing new design standards based on the BS ENs and withdrawn BS design standards. If this is the case, detailed justification will need to be submitted.

You should ensure that designers are familiar with the codes that they use for design.

All computer analysis should be compatible with the design standard being used.

You may wish to clarify with your insurers that the code used is acceptable to them.

Designs should be submitted using the UK National Annex only. The use of an inappropriate National Annex or the CEN recommended values would invalidate your design and we would be obliged to ask you to reconsider your design philosophy.

If you are in any doubt

You can contact one of our team for further advice on this subject by telephoning 020 7332 1000, or by emailing District Surveyor. 

The number and type of sanitary appliances required in non-domestic situations is covered by various regulations, HSE publications and British Standards. This guidance note is intended to give you some background to them and their use, in non-domestic buildings, so that you can make more informed decisions when calculating your toilet provisions, designing their layout and making a Building Regulations submission.Because we understand how important the sanitary provisions are to a scheme design, we are more than happy to discuss your proposals prior to the Building Regulations application being made. Therefore if you have any queries or would like to discuss your project, please contact us.

What sort of information do we need to assess your proposals?

To enable us to assess your Building Regulation application, we need to know what the intended use of the premises is, for example, restaurant or office, the number of floors and their anticipated layouts, indicating if the toilets are in common parts and their availability. And, of course, how many people are likely to use them and what gender ratio you have assumed. This is to enable us to assess your submissions more effectively and to give a more targeted and efficient response.

This information does not have to be submitted at the time of the application

Because toilet provision calculations are normally required in response to conditions that we attach to an approval, they do not need to be submitted with the application. Therefore your calculations for the proposed sanitary appliances and their layouts can be submitted when the design is sufficiently developed. However, you should ensure that this is done as early as possible and certainly in advance of the works commencing, this is particularly relevant to fast track projects or where there may be some uncertainty.

What legislation and guidance applies?

The minimum requirement for staff in non-domestic buildings may be as set out in the Approved Code of Practice (ACOP) for Workplaces that support the Workplace (health, safety and welfare) Regulations 1992. Guidance on these minimum requirements can be found at the HSE website.

For other types of buildings or if the applicant wishes to provide more than the minimum requirements as referred to in the above ACOP to deliver equivalent provision for both men and women, reference should be made to BS 6465-1:2006 + A1:2009 (sanitary installations. Code of practice for the design of sanitary facilities and scales of provision of sanitary and associated appliances).

The current Workplace (health, safety and welfare) Regulations 1992 do not indicate the method of calculating the disabled provision within the overall sanitary provision for a building. However, we have taken the view that when unisex/self contained toilets are provided and there are more than 5 WC and WHB’s in the building, the unisex/self contained toilets can be calculated for 25 persons split the same as the ratio between male and female (12-13 male and 12-13 female).

There were some changes between BS 6465-1:2006 and the introduction of BS 6465-1:2006 + A1:2009. In the 2006 edition (now superseded by 2009 edition) tables 3 and 4, an increase of 25% should have been allowed where unisex/self contained toilets are provided (clause 5.3.3). However, in the 2009 addition clause 6.4.1 e), where unisex/self contained cubicles are proposed, the provision may be calculated on 100% of the population. The number of toilets does not therefore need to be increased as recommended by clause 5.3.3.