Application of building regulations to domestic extensions: EIR release

Information request and response under the Environmental Information (Scotland) Regulations 2004.

Information requested

Information on the application of building regulations to domestic extensions and the recent change to published guidance and 'removal of the ability to use improvements to an existing house to compensate for areas of glazing in an extension which are more than 25% of the floor area'. You raised ten specific questions on, or relating to, this change. These are listed below, with a response on each point.

As the information you have requested is ‘environmental information’ for the purposes of the Environmental Information (Scotland) Regulations 2004 (EIRs), we are required to deal with your request under those Regulations. We are applying the exemption at section 39(2) of the Freedom of Information (Scotland) Act 2002 (FOISA), so that we do not also have to deal with your request under FOISA.

This exemption is subject to the ‘public interest test’. Therefore, taking account of all the circumstances of this case, we have considered if the public interest in disclosing the information outweighs the public interest in applying the exemption. We have found that, on balance, the public interest lies in favour of upholding the exemption, because there is no public interest in dealing with the same request under two different regimes. This is essentially a technical point and has no material effect on the outcome of your request.


Most of the information you have requested is available from the Scottish Government website and links to these resources are noted in our response which follows. Under regulation 6(1)(b) of the EIRs, we do not have to give you information which is already publicly available and easily accessible to you in another form or format. If, however, you do not have internet access to obtain this information from the website(s) listed, then please contact me again and we will send you a paper copy.

Information not available from such sources is attached as annexes to this response.

a) What was the motivation for making this change (i.e the change from 6.2.9 to the new 6.2.8) – please describe the reasoning?

The motivation for the change described (improvement and rationalisation of minimum U-values for work to domestic buildings) is noted in section 3.2.2 of part 3 of the Consultation document, published at Part 3 – Energy, all buildings - Building regulations - energy standards and associated topics - proposed changes: consultation. This includes a reference to the values applied from 2015 for poorer performing dwellings. Question 21 of the Consultation package seeks views on this proposal.

In summary this notes that, with further increase in the level of fabric specification sought from work to new or existing buildings, it becomes more challenging to set or justify more than one set of values, as such elemental standards become more challenging to achieve.

b) When was this change first announced, i.e. when was the Feb 2023 first published? Please could you send me a copy of the means by which this announcement was made?

The initial notification was made in June 2022 within the Scottish Government response to the consultation (page 9), published at Energy Standards Consultation 2021 Scottish Government Response June 2022. The December 2022 Domestic Technical Handbook which includes the amended clause 6.2.8 cited in your query was first published on 15 June 2022. This publication was withdrawn and replaced on 24 February 2023 with the February 2023 version of the Domestic Technical Handbook, which reflected the amended in-force date for the revised standards, changed from 1 December 2022 to 1 February 2023. The text in clause 6.2.8 was unchanged by this republication.

c) Was there any consultation about this change? If so, please could you send me a copy of how the consultation was conducted and a collation of the results?

Information on the consultation exercise which led to these changes is published at This includes the consultation proposals, responses received, the Scottish Government response and links to all key documents, including the initial publication of the revised Technical

Handbook (December 2022). The consultation response, summarising the process and action to be taken forward was published at Energy Standards Consultation 2021 Scottish Government Response June 2022.

d) Please could you send me a copy of all internal research, discussion and papers relating to this change from your department?

The subject in question – review of maximum U-values for work to existing domestic buildings was covered by Working Group paper WG 17. The proposal on the topic and paper WG 21, the minute of the meeting at which this topic was discussed (see item 4 in each paper) are attached as Annex A and Annex B.

e) Was there any attempt to notify architects and developers about these changes? Please describe all methods that were used and when?

Notification of the publication of the consultation was made to members of standing groups liaising with Building Standards Division, parties who had previously registered an interest in notification on building standards changes and also through social media. Notification included the Royal Incorporation of Architects in Scotland, who were also an organisation participating in the energy review group which led to the published consultation and final proposals. A series of seven open online sessions to support discussion on the changes were also arranged and undertaken between 14 September and 5 October 2021.

Notifications of such activities are not generally retained as documents of record. As examples of such activity, we attach two retained examples of notification, one on the issue of the consultation and one on the extension of the consultation period and availability of calculation tools, as Annex C and Annex D.

f) Is there any plan to review this in the future? Are you interested at all in feedback? If so how will this be gathered?

You may be aware that Scottish Ministers have committed to a further review of energy standards set by building regulations following the statement to Parliament by Patrick Harvey, Minister for Zero Carbon Buildings, Active Travel and Tenants’ Rights, of 10 January 2023 – available at Official Report ( Further information on the scope and timetable for this review will be agreed with Ministers and issued in the coming months. There is currently no programmed work to consider this specific topic as part of that review.

We are always interested in feedback on both the consultation process and the effects of changes, once introduced. Outwith any specific consultation exercise, this can be sent to and will be allocated to the relevant official for consideration and response.

g) Can you suggest any alternative ways that we can achieve glass areas in an extension of say, 50-60% of the floor area? I am aware that the Standards allow the use of SAP, but as I am sure you are aware that won’t work for a period property where existing walls are hard to insulate. There are anyway considerable concerns in the industry about the accuracy and benefits of SAP.

h) The Building Standards allow for ‘Alternative Solutions’ to be provided as an alternative method of compliance. Can you please describe which alternative solutions for this Standard you would consider acceptable where an extension to a Category A or B Listed house is proposed which has glazing of say 50% of the floor area? (I note that the compensatory approach for an extension alone only works to about 45% of the floor area, even with triple glazing).

I) For example if a developer were to propose energy saving measures be introduced to an existing listed building which achieve a saving of say, five times the amount of energy lost by the excess above 25% of the floor area, would you consider that an example of a satisfactory Alternative Solution?

These three question do not seek information we hold, but an opinion on an alternate approach to compliance. We would therefore apply an exception under regulation 10(4)(a) of the EIRs as we cannot provide information we do not hold. Instead, we can offer general advice on the intent behind published standards and guidance.

The provisions under discussion relate to guidance which provides a means of meeting standard 6.2 (building insulation envelope). It is not the role of The Scottish Government to offer such suggestions or discuss alternative solutions to demonstrate compliance with building regulations. You may be aware that alternative means of demonstrating compliance with the functional standards within schedule 9 to regulations 5 of the building regulations is a matter for discussion with your local authority verifier as the organisation responsible for determining whether works submitted for building warrant will comply with the building regulations.

Where compliance of an alternative solution is in doubt, the matter can be referred to Scottish Ministers for a Ministerial View - details available at improving-building-regulations/.

We would note that that the compensatory approach can still be applied to the specification of an extension, as was the case under the previous 2015 building standards. This approach is now set out within Annex 6.A of the February 2023 Domestic Technical Handbook.

j) Why are there two updates to the Standards published and scheduled for 2023? What benefit would we achieve by using the Feb 2023 Standards now, rather than just going straight to the July 2023 version (I ask in order to save me having to read through all the lists of changes at the start of each section). Is this not seen as being somewhat confusing for both applicants and verifiers?

You may be aware that the implementation date of the revised standard was amended from 1 December 2022 to 1 February 2023 due to issues encountered in the delivery of third party energy assessment tools. The February 2023 version reformats the Handbook and incorporates small changes to text on issues such as alignment of guidance with the implemented SAP and SBEM energy assessment tools.

The June 2023 Handbooks implement a further change to the standards, introducing standard 7.2 (electric vehicle charging), a topic also consulted upon in July 2021 but progressed separately as a Transport Scotland-led change. The Scottish Government response on that issue was published in August 2022.

The scope of application of each version of the Handbooks is noted by reference to 'applicable from' dates on each page of the publication to avoid confusion in application.

A short primer on the topics subject to change in both the February 2023 and June 2023 Handbooks are published on our 2022-23 changes webpage.

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