Passivhaus compared to the proposed FHS 2025

The Passivhaus Trust has just published a position paper comparing the performance of Future Homes standard proposals with the Passivhaus Classic standard. Based on these findings, the Passivhaus Trust makes some key policy recommendations.

Position paper

The position paper evaluates the Future Homes Standard (FHS) 2025 against Passivhaus Classic, comparing energy performance, heating costs, and carbon emissions. The analysis models two FHS options – one with solar photovoltaics (FHS PV) and one without (FHS no PV) – against Passivhaus.

Findings show that both FHS options result in higher annual energy costs than 2021 regulations, with FHS no PV nearly doubling costs in some cases. In contrast, Passivhaus Classic matches or outperforms FHS PV using only improved building fabric, delivering long-term energy savings without reliance on PV, which is not always feasible and may degrade over time. This paper highlights how Passivhaus, without solar photovoltaics (PV), offers lower running costs, better occupant comfort, and the same or lower carbon emissions than the two potential FHS options.

Recommendations

To ensure affordability and long-term sustainability in UK housing, the Passivhaus Trust recommends that:

Future Homes Standard dwellings should cost no more to heat than those built under current building regulations.This would require Passivhaus-level fabric improvements, where solar PV is impractical.
Passivhaus Classic should be deemed to comply with Approved Document L when the Future Homes Standard is introduced.

Download the NEW paper to understand potential problems and solutions with the poposed Future Homes Standard proposals.

The paper's author, Rachell Mitchell, also presented the key findings at Futurebuild 2025: