The Scottish Government has opened the stage two consultation on a Scottish equivalent to the Passivhaus standard, seeking views on proposed energy and environmental performance targets and on an enhanced compliance process1.
The commitment dates from December 2022, when Ministers undertook to give effect to Alex Rowley MSP's Proposed Domestic Building Environmental Standards (Scotland) Bill1. Stakeholder engagement began in January 2023 and an industry working group was formed in June 20231. A stage one consultation followed in July 2024, asking how the standard should be delivered through building regulations and on the proposed timetable1. The Building (Procedure) (Scotland) Amendment Regulations 2024 were laid in December 2024, requiring design and construction stage compliance statements on specified energy and environmental standards, with a coming into force date of 31 March 20281.
That timetable has now moved. The Scottish Government states that development of the stage two proposals, supporting guidance and assessment tools has taken longer than anticipated, and it now aims to publish guidance and approved methodologies under standard 6.1 in Autumn 20271. To maintain what it calls a sufficient industry preparation period, it will amend the implementation date in regulations to Autumn 20291. It adds that it will consider introducing the standard in full, phasing it in, or supporting voluntary adoption before compliance becomes mandatory1.
"This stage two consultation seeks views on proposed energy and environmental performance targets for the new standard and on proposals for an enhanced compliance process, including guidance to support the requirement to submit energy and environmental design and construction statements. Items related to indoor air quality and overheating are also presented."
The consultation sets out five energy and environmental considerations for a proposed Building Standards Energy and Environmental Compliance Handbook: airtight construction, high performance insulation, thermal bridge free design, ventilation and optimised energy use1. Interim domestic and non-domestic energy performance calculation methodologies are presented as work in progress, to be developed further before adoption as approved methodologies prior to implementation1.
Separate technical analysis published on 24 July 2026 by AECOM and Currie and Brown modelled three performance specifications (Business as Usual, Good practice and Best practice) against three heating technologies (air source heat pump, direct electric heating and district heating network connection) using SAP 10.2, HEM v0.33 with the Future Homes Standard wrapper, and PHPP v10.62. It found the Best Practice specification achieved the Passivhaus space heat demand target of 15kWh/m2/yr in PHPP for half of the archetypes assessed, representing circa 40% of the new build housing stock2. The air source heat pump consistently produced the lowest Dwelling Delivered Energy Rate across the archetypes modelled2.
On cost, the analysis found that neither the good nor best practice standards deliver a net benefit in comparison to current regulations when modelled with HEM or SAP; using PHPP, the good practice standard achieves a £1million net benefit but there is no net benefit for the best practice standard2. It also notes that tariff variability, which may be challenging to account for in Building Regulations compliance calculations, could significantly impact actual dwelling fuel bills2.
| Specification | Space heat demand target in PHPP | Net benefit against current regulations |
|---|---|---|
| Good practice | Not achieved for all archetypes | £1million using PHPP; no net benefit using HEM or SAP |
| Best practice | 15kWh/m2/yr for half of archetypes assessed | No net benefit under any model |
Why it matters for households
Scottish building regulations set minimum standards for new buildings and for new work to existing buildings1. The proposed standard is aimed at lowering energy demand and running costs and at assuring a healthy indoor environment1. The Scottish Government states it will support statutory 2045 Net Zero targets, 2040 Fuel Poverty targets and 2030 Child Poverty targets, alongside objectives in the Environment Strategy, Heat in Buildings Strategy and Housing to 20401. For a household, the practical effect of a tighter fabric and ventilation standard is a home that needs less energy to stay warm, though the cost analysis indicates that whether that translates into lower bills depends on the heating technology installed and on tariffs, which the research describes as variable and hard to capture in compliance calculations2.
The standard as consulted on applies to new buildings and new work, not to existing homes. The separate New Build Heat Standard already bans direct emission heating systems in new homes, and the interaction between that standard and the notional house specification has been contested: Solar Energy UK reported in January 2024 that the boiler ban was enacted while the Notional House Specification was left unchanged, which it said would drop solar PV from the notional house in Scotland for the first time since 20153. That account is a trade body's assessment and is not reflected in the Scottish Government's own consultation material1.
What happens next
Guidance and approved methodologies under standard 6.1 are targeted for Autumn 2027, and the implementation date in regulations is to be amended to Autumn 20291. The Scottish Government has said responses are usually published some months after a consultation closes, with an analysis report following later1. No decision on whether the standard will be mandatory, phased or initially voluntary has been reported1.
Sources3 cited
- [Building Regulations: The Scottish equivalent to the Passivhaus standard: Stage 2
- Building regulations - new domestic buildings: identification and assessment of energy standard improvements - gov.scot, gov.scot
- New Scottish Building Regulations Torpedo a Solar Success Story • Solar Energy UK, solarenergyuk.org