Determining the principles for a Scottish equivalent to the Passivhaus standard - Analysis of Consultation Responses

7. Conclusion

Many individuals and organisations with detailed knowledge participated in the consultation, sharing their views on defining a Scottish equivalent to the Passivhaus standard. This report provides a high-level summary of the consultation responses. For more detail, readers are encouraged to read individual responses where permission was given for publication via the Scottish Government's consultation website.

More respondents disagreed than agreed with the proposals for what a Passivhaus 'equivalent' should mean and the suggested statements on what an 'equivalent' should consider. However, this disagreement appears to be based on opposition to specific aspects of each. Many respondents felt that an 'equivalent' should retain a similar level of prescription as Passivhaus on key energy-related elements of building specification, with widespread disagreement with the fourth^[8] and fifth^[9] bullet points in the list of considerations. Beyond these concerns, support was expressed for other elements of a proposed 'equivalent'.

There was evidence of a desire to support other aligned approaches to deliver improvements on current outcomes. For example, respondents advocated the use of PHPP as a calculation tool or called for other calculation tools to be approved for use, called for the use of absolute targets for new buildings rather than the existing approach of using relative targets, and opposed the proposal to cover only delivered energy with calls for unregulated energy to be included as well. There was also widespread support for introducing a prescriptive space heating demand limit for new buildings and for applying regional climate data within the approved calculation methodologies.

Several respondents reported that they already exceed backstop values for fabric performance, either by following Passivhaus standard or higher standards, and expressed support for targets, standards or regulation to limit fabric infiltration through building standards to improve build quality and performance and comfort levels. There was also extensive agreement that MVHR is the best way to achieve effective ventilation of new buildings, though there were some calls for flexibility in ventilation approaches and the need to consider occupant comfort.

Many respondents supported the idea that Passivhaus Certification could be a feasible alternative for complying with energy demand standards, though concerns about costs and practical challenges were noted alongside some calls for flexibility. Throughout the consultation, suggestions were made for improving industry training and upskilling, providing occupant or user guidance, and addressing key considerations such as how to achieve airtightness, and incorporating thermal comfort, air quality, and embodied carbon into building standards.

When considering the case for a strengthened compliance process with associated guidance, there was widespread support for the scope and recommended actions outlined in the consultation paper. Respondents were clear about the need to apply provisions from the early design stage to completion and handover, repeatedly emphasising the need for continuous quality assurance and collaboration between all those involved. Some concerns were expressed, however, about the need for clear definitions of roles and responsibilities, and the potential cost and workload implications of additional monitoring and verification processes.

A majority of respondents supported the proposed phased approach to implementation, with the timeline allowing the industry time to prepare, upskill, and develop supply chains. However, some emphasised the need for clear guidance, financial support, and training programs to ensure successful adoption. Concerns were raised by some about the phased approach either being too slow and delaying necessary changes, or too quick and potentially causing economic and viability issues.

It is important to note that the 24 campaign responses submitted by contractors and developers expressed significant opposition to the proposals. These responses highlighted the positive effect of existing regulation on improving the energy efficiency of new buildings in Scotland. Given this progress, it was suggested that further regulation may have limited further impact on energy efficiency, but a significant impact on the supply of new homes in Scotland.

Overall, the key message is that while there is support for the proposals among many groups, respondents identified multiple issues which they felt need to be considered in advance of progressing the proposals. The responses provide valuable and informative evidence for the Scottish Government to draw on when preparing amendments to regulations, to continue stakeholder engagement and to inform the structure and content of next year's consultation.