A new NHBC Foundation report details the UK's journey towards Passivhaus

The NHBC Foundation report, ‘The UK’s progress towards a Passivhaus standard in new homes’, notes that the UK has seen a significant increase in Passivhaus-certified buildings over the last decade, from just 165 in 2013 to over 2,900 in 2024, with more than 8000 units currently in some stage of development. However, the adoption of this approach to the design and construction of new homes has been slower than initially expected, due in part to challenges around education, costs and the need for cultural and structural change in the construction industry.

Part of the issue has been that no nation within the UK has made Passivhaus a requirement on new homes. Scotland has committed to introduce a ‘Passivhaus equivalent’ standard by December 2024. Some Passivhaus principles have been incorporated into the building regulations in England, Wales and Northern Ireland. However, there are currently no plans to make Passivhaus or an equivalent standard mandatory.

In addition to this, one of the main obstacles identified within the report is the significant transformation required in construction processes as well as in the supply chain to achieve the stringent targets. Skills shortages and workforce availability were also highlighted as potential issues. However, it also notes that innovations such as modular construction show promise in overcoming some of these problems.

Also highlighted in the report are the issues that can arise if homeowners do not understand how to manage and maintain such high-performance homes. It gives the example of the mechanical ventilation with heat recovery (MVHR) system malfunctioning. If this goes unnoticed or unaddressed by the owner, it can quickly lead to a serious condensation build up, which will impact the fabric of the property as well as the health and wellbeing of the residents.

Cost also remains a significant barrier. While the increase in cost has reduced in recent years, Passivhaus homes are estimated to be 4% to 19% more expensive to build than homes that comply with current Part L standards. However, the Passivhaus Trust has found that Passivhaus certified properties are valued around 5% to 15% higher, suggesting that environmentally conscious buyers are willing to pay for the benefits it offers. Despite this finding, prospective buyers who prioritise the energy efficiency of the property are still in the minority. The NHBC Foundation cites research conducted by NatWest that found only 40% of buyers consider an EPC rating as ‘very important’.

It is now well understood that the UK construction industry must change if it is to deliver the net-zero homes required to meet environmental targets. Adopting Passivhaus principles is one route to achieving this, and while the foundations have been laid, this report shows that there is still some way to go before it becomes the norm.