The Secretary of State for Energy and Climate Change, Chris Huhne, has described the Passivhaus comfort and energy efficiency standard as “a watershed moment in our relationship with the built environment” and said he “would like to see every new home in the UK reach the standard.” Mr Huhne was speaking at the first ever UK conference devoted entirely to discussion about the Passivhaus standard, which which was held at Islington Town Hall on Monday 11th October. The main topic on this conference was building new houses that will incorporate the Passivhaus standard as a way to improve the already made concept of eco homes.
The Passivhaus standard is a comfort and energy efficiency standard for both new build and retrofit which was designed by German architectural engineers more than 20 years ago.
Thick walls, triple glazing, heat recovery ventilation and, where applicable, careful solar orientation of the building means, in most cases, there’s no need for central heating or air conditioning – the warmth of human bodies and electrical appliances is enough. There are now thought to be about 100 Passivhaus buildings either completed, under construction or being planned in the UK. It is estimated that there are tens of thousands in Europe. The new concept of eco-friendly home is not something new, but rather a redesigned concept that could have a huge positive impact on the environment preservation.
Mr Huhne promised the introduction of a “minimum standard for fabric energy efficiency” as part of the government’s forthcoming Green Deal. He told conference delegates that the Green Deal would be “underpinned by a strong framework of standards and accreditation – for assessors and installers” and that “eligible energy efficient measures [would] be focused on the building fabric, and [would] have to be installed to the highest standard.”
Alexis Rowell, the Director of the UK Passivhaus Conference, said: “Whilst I support the principles of the Green Deal, I am concerned that it will allow householders to install a potpourri of measures that will not add up to a coherent whole; using builders who will not have to follow a measurable, energy-based route map; and that consequently the Green Deal will not significantly reduce energy demand. I’m delighted to hear that there will be a minimum standard for fabric efficiency, but I’m worried that unless the standard uses Passivhaus design principles it will not get us anywhere near the 80% cut in emissions needed by 2050.”
Mr Rowell went on to say: “Chris Huhne described heat recovery ventilation as an “expensive, nice-to-have add-on” but it’s not. In my opinion there’s no conceivable way to reach an 80% reduction in carbon emissions across the UK building stock without using heat recovery ventilation. I’m delighted that he’s taken on board the message that eco bling – mini wind turbines etc – isn’t the answer, but I do think he needs to think again about heat recovery ventilation.”
Mr Huhne also said that “a new paradigm was needed in housing, where value is measured in the running costs to 2050 and beyond, and where we look at total cost – construction cost and running cost.” Mr Rowell welcomed this statement and said: “As the Secretary of State pointed out in his speech the cost of building to the Passivhaus standard is coming down all the time.
It’s already the case in the UK that when future energy bills are included in build cost Passivhaus developments are cheaper than conventional build, but in both Germany and Belgium Passivhaus architects are achieving build costs that are lower than conventional build even before accounting for future energy bills.
In his opening speech to the UK Passivhaus Conference Mr Rowell called on the UK government to: “introduce the Passivhaus standard into building regulations for new build by 2016; to work with the UK building industry to provide training on the Passivhaus standard; and to use the Passivhaus retrofit standard (a slightly easier-to-hit target than the full Passivhaus standard) for the government’s forthcoming Green Deal.” Although it takes a lot of effort to make this standard become a default one, the way for implementing is bright. It will not take long before the every new house that is going to be built would use this standard.
Answering questions after his speech Mr Huhne said he thought the Passivhaus standard was probably too tough and too expensive for most British refurbishments but he promised to visit any retrofits that proved him wrong. Mr Rowell later told delegates: “Our challenge now is to provide the Secretary of State with the evidence and the spreadsheets to show that retrofitting using Passivhaus design principles does not have to be prohibitively expensive, will lead to dramatically more comfortable houses and is the only way to reduce the energy demand of existing buildings by 80% or more.
Notes to editors:
1. The UK Passivhaus Conference is a biannual not-for-profit event. The aims of the conference are to further knowledge, to stimulate debate and to press for change.
2. The PH standard requires that the total energy demand for space heating and cooling be less than 15 kWh/yr per m2 of floor area and that the total primary energy use for all appliances, domestic hot water and space heating and cooling be less than 120 kWh/m2/yr. There must also be no more than 0.6 air changes an hour at standard pressure (50 Pa), which is more than ten times better than the average UK new build. This last point is why the creator of the standard, Prof. Wolfgang Feist, always describes it as first and foremost a comfort standard. No draughts and heated fresh air means comfort. There’s also now a trial PH retrofit standard which is slightly easier to reach (25 kW/h/m2 and 1.0 air changes per hour).
3. In December 2009 the BRE released a Passivhaus Primer which said: “The fabric performance requirements required for level 6 of the Code are based upon the PassivHaus standard. With the exception of flats, it is not generally possible to achieve Code Level 6 without adopting a performance specification similar to Passivhaus.”