Passivhaus has been an accepted building method in Germany for much longer than in the UK and recent NHBC research highlights the lessons UK construction can learn from the experience of those using the standard in Germany and Europe.
- Passivhaus likely to increase in popularity
- Major issues facing the UK market
- The cost factor
The UK government’s pledge that all new homes will be zero carbon by 2016 has led housebuilders, developers and social housing providers to explore new ways of reducing the energy consumption of the houses they build.
This has led to increased consideration of Passivhaus standards. Developed in Germany, Passivhaus sets very high requirements for energy-efficient design and construction. The focus is on minimising the requirement for space heating and cooling, and hence overall energy consumption.
Passivhaus likely to increase in popularity
Last year, 165 Passivhaus buildings were completed or under construction in the UK, but this figure is likely to treble to around 500 by the end of 2013. Worldwide, some 37,000 Passivhaus buildings have been built.
“The report also finds that the German population has a stronger interest in the environment”
The NHBC Foundation’s recent report, Lessons from Germany’s Passivhaus experience, provides an overview of the experience gained to date from Passivhaus in Germany and elsewhere in Europe.
The report found that the Passivhaus standard is a viable means of delivering low-carbon housing and the vast majority of people (92 per cent) who live in these homes are pleased with them.
Major issues facing the UK market
But it is also clear that there are significant issues to overcome if these ultra-low energy homes are to take off in the UK.
These challenges include the need to develop a more rigorous approach to quality assurance, high compliance standards and the extra costs associated with building houses to the Passivhaus standard.
A significant factor in the uptake of Passivhaus in Germany has been the availability of reduced interest rate loans and grants; however, just one such loan scheme is available in the UK and no capital grants are available for energy-efficient new-build projects in the UK.
The report also finds that the German population has a stronger interest in the environment and a general enthusiasm for higher specification products.
Looking at the UK, Passivhaus homes have to verify compliance with building regulations as well as the high Passivhaus standard; in Germany, the Passivhaus certification automatically confirms compliance with building regulations.
The cost factor
The report also finds that the cost of building a Passivhaus home in Germany is now estimated at 3 to 8 per cent more than building a home to the building regulations (known in Germany as EnEV).
It is clear that the popularity of Passivhaus in Germany has been largely due to a combination of social, political and financial circumstances that are specific to the country.
Although the Passivhaus movement in the UK is in its infancy, there are lessons that we in the UK can learn from the attention to detail inherent in the Passivhaus approach in the run-up to the government’s 2016 zero-carbon homes target.
But there are still major issues for Passivhaus to overcome before it is fully accepted in the UK and it is questionable whether these homes are a realistic solution for the volume market at present.
Neil Smith is group research and innovation manager at the National House-building Council