How Passivhaus technology will help housing associations fight climate change
There are 21m homes in the UK – and the majority leak heat like a
sieve. No wonder the housing sector contributes to more than a quarter
(27%) of our UK CO2 emissions.
The government has committed the UK to reduce CO2 emissions by 80% of 1990 levels by 2050 and housing associations are aware of their responsibility. Only last year, the National Housing Federation stated that dealing with climate change is "an absolute necessity". However, we need to up our game. With present technology and inadequate building and planning regulations, we'd be lucky to get half way to the target.
The first step is to re-examine how to stop homes from leaking massive amounts of heat and energy. With around 75% of our housing still to be in existence in 2050, we should focus on a 'fabric first' insulation approach to create air-tight, energy-efficient properties.
There has been much talk within the sector of Passivhaus and I believe it's imperative that housing associations embrace these principles. Passivhaus is about using the world's best insulation technology to fit heavily-insulated housing fabrics, super-efficient windows and doors, and hyper-effective heat preservation systems.
The results are clear, Passivhaus cuts home energy consumption by up to 90% - around double that achieved by standard everyday insulation methods. However, while Passivhaus projects are more common across the rest of Europe the number of Passivhaus-certified buildings in the UK can be counted on one hand. Plus, our understanding of Passivhaus remains desperately low. This has to change.
What's holding us back is the high cost of top-end insulation technology. While the cost-effectiveness of new-build Passivhaus homes is increasingly being recognised, to retrofit a home adopting Passivhaus is unaffordable (£35,000-£100,000) due to low demand for products and lack of a suitably-skilled construction industry to design, supply, install, and service a low-to-zero carbon building.
So, what's to be done? Housing associations should work together better for a start. While there are a number of housing association who are leading the way on low-carbon housing projects there's not an effective national forum to share research and findings.
Last year Orbit partnered up with Coventry University to study in detail how best to retrofit some of our housing stock to Passivhaus standards. The study's aim is to answer questions such as how effective are Passivhaus technology and principles? Is it best to triple glaze immediately, or wait until after double-glazed windows are past their optimum-performance date? What are the costs and benefits of making a Victorian property air-tight? I envisage that deciding to retrofit to a certain percentage - say 90% - of Passivhaus standards will be most cost-appropriate for housing associations.
That leaves us with the question of how to reduce the cost of appropriate technology? Firstly, if housing associations can roll out Passivhaus among their 2.5million homes, then demand will increase. This will lead to a profit incentive for manufacturers to produce more top-end technology in the UK, provide homeowner confidence, and so stimulate the market.
Secondly, costs will fall if the government ramps up building and planning regulations to reflect Passivhaus standards. For example, doors, windows and roof insulation must be radically more effective at preventing heat loss than those presently on the mass market. In turn, installers must be trained and accredited to provide the level of quality necessary so they will become as used to installing Passivhaus technology as they are, for example, standard gas central heating.
To help recuperate retrofit costs, housing associations will need to consider applying a service charge to tenants balanced against the savings on heating bills. A small annual service charge can be a negligible amount compared to that year-on-year saving. Also, I emphasise, it is about housing associations taking a leading role in preventing dangerous climate change. It's an obligation we cannot ignore.
In its agreement, the coalition government stated dangerous climate change "is one of the gravest threats we face". This recognition and rhetoric is fine, but it is action we need. For the housing sector to meet its duty of cutting CO2 emissions by 80% housing associations need to take the lead and embrace Passivhaus over the next 40 years.
That's the challenge we face.

John Barnham is head of sustainable investment at Orbit Heart of England housing association
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