Scottish government consults on Passivhaus Standard equivalent

The Scottish government is seeking industry views to determine the principles for a Scottish equivalent to the Passivhaus Standard in the first of a two-stage consultation. 

The first stage, which closes on 23 October, will also seek responses to the implementation of the 2023 energy standards to inform the development of a stage 2 consultation next year. This second consultation will set out the details of proposed new standards or performance targets. 

The government has ambitions that Scotland will become a net-zero nation by 2045 and the aim of both consultations is to consider the technical, commercial and wider implications of improvements to building regulations within its broader climate change action. 

In December 2022, the then Minister for Zero Carbon Buildings, Active Travel and Tenants’ Rights confirmed that, in response to Alex Rowley MSP’s Proposed Domestic Building Environmental Standards (Scotland) Bill in May 2022, the administration would create subordinate legislation to implement his final proposal by 14 December this year. 

The Scottish Labour MSP for Mid Scotland and Fife had called for the introduction of “new minimum environmental design standards for all new build housing to meet a Scottish equivalent to the Passivhaus standard, in order to improve energy efficiency and thermal performance”.

As part of the administration’s commitment to meet the December 2024 deadline, the government began a further review of energy standards in building regulations in early 2023. The purpose of this review was to consider additional improvements to the standards and processes set in The Building (Scotland) Regulations 2004 (as amended) and associated regulations with a focus on two outcomes.

The first is improvements to the setting of energy and environmental (ventilation) performance standards for new buildings, leading to lower energy demand (and reduced running costs) and a healthy indoor environment. 

The second outcome is improvements to the design and construction process to give greater assurance that compliance, and therefore the performance sought, is delivered in practice.

In June 2023, an industry working group was set up to offer advice and expertise to the Scottish government and to define how an equivalent to the Passivhaus Standard will look north of the border. 

For buildings to achieve the Passivhaus Standard, they need to meet certain requirements. As the Passivhaus Trust explains, this is achieved through high standards of insulation, airtight building fabric, addressing ‘thermal bridges’ in construction, and the use of  a mechanical ventilation system with highly efficient heat recovery.

In April this year, the Scottish government implemented the New Build Heat Standard through the building regulations. This requires that all new buildings must no longer use ‘direct emission heating systems’ for space or water heating or cooling. 

The Scottish government has said that it plans to continue to develop the proposals for the Passivhaus equivalent during and after the consultation period. The consultation sets out the proposed delivery timetable beyond December 2024. 

The Passivhaus Trust welcomes the consultation and said that it would provide a detailed response in mid-August. 

Commenting, Chief Executive Jon Bootland, said: “The Passivhaus Trust believes that, while there are some positive options towards a Scottish Passivhaus equivalent outlined in the consultation proposals, what is being proposed could still fall significantly short of the intended aspirations.”

For example, the Passivhaus Trust welcomes the inclusion of a proposal for certified Passivhaus homes to be considered ‘deemed to satisfy’ Scottish building standards in the consultation questions and its exploration of quality assurance processes. 

However, the UK Passive House Organisation says the proposals for modelling tools and targets are not sufficient to achieve a genuine Passivhaus equivalent.

Image credit | Tom Manley