Energy Standards Review - Scottish Passivhaus Equivalent Working Group minutes: February 2025

Attendees and apologies

• Alan McAulay, Building Standards Hub
• Caitriona Jordan, Built Environment – Smarter Transformation
• Cassandra Dove, Scottish Federation of Housing Associations
• Colin Sinclair, Building Research Establishment
• Daniel Foulds, Scottish Government
• David Melhuish, Scottish Property Federation
• Ingrid Berkeley, Chartered Institution of Building Services Engineers
• John Smith, Structural Timber Association
• Jonathan Hines, The Passivhaus Trust
• Mark Roberts, Welsh Government
• Michael Barton-Maynard, Scottish Government
• Michael McGurk, Scottish Property Federation
• Patrick Brown, The Scottish Heads of Property Federation
• Paul Leask, Rural and Islands Housing Association Forum
• Robert Toomey, Royal Institution of Chartered Surveyors
• Ryan Cossar, Scottish Futures Trust
• Sarah May, Chartered Institute of Architectural Technologists
• Stephen Garvin, Scottish Government (co-Chair)
• Stephen Good, Built Environment - Smarter Transformation (co-Chair)
• Steven Fawcett, Homes for Scotland
• Steven Scott, Scottish Government
• Stuart Henderson, Homes for Scotland
• Stuart MacPherson, Chartered Institution of Building Services Engineers
• Victoria Bell, Scottish Government
• Zoe Black, Royal Incorporation of Architects Scotland

Items and actions

Welcome and introductions

The co-chair welcomed the group noting that its focus will now move onto firming up the technical proposals ahead of a second stage consultation later this year, addressing the areas of attention as identified within the consultation analysis and the recommendations as agreed to within the working group’s consensus paper.

Brief introductions were provided by new and substitute members of the working group.

Stage 1 consultation and laying of amendment regulations

Reference was made to document WG 38(25).

Officials reminded members that in the lead up to last year’s consultation, the Minister for Housing agreed to split the programme of work into two stages: firstly, laying enabling regulations in December to meet the intent of Mr Rowley’s Bill, and subsequently developing the technical proposals for consultation later in 2025.

Enabling regulations were laid in December setting an implementation date of 31 March 2028. This established new requirements for the provision of Energy and Environmental Design and Construction Statements under the Building (Scotland) (Procedure) Regulations.

The Scottish Government published responses, an analysis and the first part of a response to the stage 1 consultation in December setting out the rationale for an immediate focus on amending the procedure regulations.

Officials will now focus on building up to the second stage consultation, developing the necessary guidance documents and taking forward commissions for the development of consultation versions of the compliance tools.

Separately from the Scottish Government process, working group members noted that the Scottish Parliament’s Local Government, Housing and Planning Committee issued a Call for Views on the enabling regulations. The committee sat mid-January to discuss the amendment regulations, however no issues have been raised with officials to date.

Action point 1 – Officials to engage with committee clerks to assess the current position.

Working group members were reminded that the consultation webpage remains a useful resource with the consultation analysis, responses and the Scottish Government’s response available to view. Officials noted that the part two response to the consultation will be issued via this platform later this month.

Confirming the Scottish equivalent to the Passivhaus standard

Reference was made to document WG 38(25).

Having considered feedback from the stage one consultation, officials note there is broad support for the proposals to introduce a Passivhaus equivalent standard. The following points are drawn from consideration of the consultation analysis and working group discussions:

• building standards will not mandate the requirement for all new buildings to be fully Passivhaus certified or for the use of Passivhaus certified products
• Officials will continue to work with stakeholders to develop the proposal that Passivhaus certification could offer a feasible alternative means of compliance with standard 6.1
• how compliance is demonstrated during design and construction stages of a project is a key ongoing focus. SFT has been commissioned to undertake research with the intent of developing good practice guidance, mapping this over the current building standards system
• consideration of embodied and whole life carbon emissions remains outwith the scope of this work
• there is consensus on continuing use of UK compliance methodologies on the condition that the Home Energy Model (HEM) and Scottish wrapper is robust and offers comparative levels of accuracy to that of PHPP. Programmed research will allow for an assessment of the benefits of various tools and identify what is needed to demonstrate compliance. Officials will hold further discussions with stakeholders to understand the role PHPP could play in the new energy standard
• officials intend to expand upon the Technical Handbook guidance, drawing in the building services compliance and low carbon equipment guides into the main body of the document. In addition, further guidance on ventilation and use of mechanical ventilation systems would be provided
• there was a concern that availability of multiple compliance tools may lead to local authorities requiring developers to utilise the more onerous of compliance methodologies. It was, however, confirmed that unless explicitly stated within the mandatory standard, verifiers are unable to require use of one tool over another also highlighting that alternative means of compliance can already be accepted
• concerns regarding the risk of increasing embodied carbon in new construction were countered with members noting that such issues can be mitigated through choice of construction products. Members noted that there are ongoing discussions at a UK and EU level regarding commonality of reporting practices and that there is already a requirement to consider lifecycle greenhouse gas emissions within NPF4
• it was also queried whether it was necessary to mandate the provision of energy design statements, given this is already provided by many and was it additional red tape. Officials responded by noting that energy design statements are a method of showing how compliance will be met rather than simply stating a project intends to meet the regulations. In the context of the work of SFT, the review will take account of existing good practice and therefore will have minimal impact on those already providing such information

Officials drew members’ attention to the circulated paper setting out the initial propositions for the technical elements of a Passivhaus equivalent identifying the themes to be further explored by the working group. This included:

• on calculation methodologies, BRE has been appointed to develop domestic tools, with procurement for non-domestic tools still in progress. Consideration will be given to the strengths of existing tools, focusing on what makes them robust and accurate in modelling but also any limitations of their outputs
• on metrics, there will be a continued focus on delivered energy, however, consideration will be given to how unregulated energy fits into the wider picture. AECOM will pick up on this theme during the development of the notional building model and assess risks associated with unregulated energy
• on space heating demand, there was broad support for introducing a demand limit. Research will continue to explore the pros and cons of this approach and merits of providing an airtightness target limit
• on ventilation, recognition is given to the benefits in use of mechanical systems within airtight dwellings and that there is a need for further guidance on MVHR systems. Officials plan to arrange workshops alongside the technical author for Section 3 Environment to give specific consideration of such issues

The co-chair suggested that it would be useful for SFT to present findings from its research on compliance in order that this can be considered in conjunction with the wider work of this group.

Action point 2 – Officials to invite SFT to give a presentation on relevant areas of research findings at a future working group meeting

Research update

Reference was made to document WG 38(25).

Officials providing a brief overview of the ongoing research programme with attention drawn to:

• BRE has been appointed to undertake work in relation to domestic tools with the intention that working group members are able to test this version prior to consultation. Procurement for non-domestic tools, based on the current SBEM and applying any Scottish requirements, closes today
• AECOM has been appointed to undertake work in relation to the development of specifications and cost analysis of domestic and non-domestic notional buildings. With the domestic contract complete, officials will invite AECOM to present findings to the working group in April.
• SFT continue work on developing compliance guidance and providing an overlay of existing good practice for the development of low energy buildings against the current building standards system. SFT will also support the development of guidance on Energy and Environmental Design and Construction Statements. Officials will look to present findings to the working group over the next couple of meetings
• The Lines Between were commissioned to undertake the Stage 1 consultation analysis. This contract has now ended
• Development of the final version of the compliance tools for Standard 6.1 is yet to be procured however is expected to be ready for 2026

Working group members were invited to engage with the ongoing research programme. SFT note that in relation to their commissions, eight projects across domestic and non-domestic buildings are being assessed as a sample, however they remain open to engaging with developers on the working group.

Action point 3 – Working group members are invited to express an interest in engaging with ongoing research

Programme update

Officials provided a brief overview of the updated review programme highlighting the key areas of work building up to May 2025 including:

• the immediate focus for officials is to agree and publish the second part of the response to last year’s consultation
• the development of consultation versions of modelling tools will influence ongoing timescales. Officials expect there to be time for the working group to test and provide feedback on tools ahead of the stage two consultation
• officials will look to establish a series of working group meetings between March and July to take forward discussions on the key themes previously discussed
• officials will continue to build and update the impact assessments relating to this review
• in relation to discussions around ‘Deemed to Satisfy’ approaches, officials confirmed that this would be further explored in due course 

The co-chair agreed to support ongoing discussions with working group members and to schedule additional consensus building workshops with working group members.

Confirmation of onward focused engagement

The co-chair noted that today’s discussions have been useful in reopening dialogue and engagement on this work as the focus now turns to establishing the technical parameters of the Passivhaus equivalent. Officials further noted that outputs from these discussions feed into working group papers as well as advice circulated to Ministers.

Any other business

No other business raised.

Meeting closed