The Passivhaus Trust promotes the growth of the Passive House movement in the UK (and gets the name right, too) The Passivhaus standard sets an absolute limit on the amount of energy a building can use and it is tough to achieve, tougher to do at a competitive price and tougher still to make it look good in a world where architects like to throw big windows and lots of jogs into every building. The 2014 UK Passivhaus Awards were just announced and they are interesting and instructive.
Top prize in the Bespoke (custom) category went to the "New Farmhouse" designed by Kirsty McGuire Architects. She writes:
We chose to design a modern home referring to the local farm vernacular of the west coast traditional hayshed rather than re-create a ‘traditional’ farmhouse. Using passive solar design and natural ventilation combined with heat recovery and a high performance building shell gives great comfort to the occupants and very low running costs for energy.
The house is so efficient that it would cost about US$ 400 to heat it all year electrically. I was pretty surprised when it was described as vernacular, but in the video there is a photo of a typical barn and there is definitely some allusion here. There are good reasons to use Passivhaus in the Scottish countryside, as the Trust explains:
Fuel poverty is a huge issue in rural housing in Scotland and Passivhaus was ideal as, typically for a rural property, energy supply options are limited and expensive. Not only has the demand been minimised through the fabric first design, but carefully selected renewables have been installed.
Burnham Overy Staithe
This project won the Architectural Design Category, and demonstrates a point that I keep talking about, that we should learn the lessons of old buildings. Windows used to be the most expensive part of a house; for quite a while in the UK property taxes were actually calculated on the number of panes of glass, which was a real indicator of wealth. They also are the biggest sources of heat loss, so designers tended to keep them small. In these three houses, Parsons + Whittley Architects put the vernacular design to work.
The use of flint, local red brick and clay pantiles help the buildings assimilate into the landscape and gives them a friendly, familiar appeal. The traditional deep reveals and smaller north facing windows required for the Passivhaus standard naturally reflect what our forebears understood about shelter and consequently the scheme had little difficulty in delivering this most modern standard within a traditional context.
Once again we see how Passivhaus can be used in social housing; instead of building to code minimum to minimize capital cost, they worry about the long term operating costs.
The North Norfolk coast has a significant proportion of second homes driving housing costs beyond the reach of local people. Hastoe Housing Association’s programme of delivering Passivhaus as a means of addressing fuel poverty in the affordable housing sector has rarely been more appreciated than at Burnham Overy Staithe.
More at the Passivhaus Trust
Then there is the exception that proves the rule, that yes, Passivhaus designs are boxy and design-challenged. On the other hand, it meets the Passivhaus standards using the Beattie Passive House system, and was built by a foreman who had two weeks training and four 17 year old kids who learned on the job, framing the houses in just five days. It then passed all the Passivhaus tests, something that experienced contractors often fail to do.
Quality control is ensured with independent structural sign off, thermal imaging and air tightness testing, all provided as standard. This adaptable system transforms any design into high-performance, low-cost homes using semi-skilled labour as well as traditional and readily available construction materials.
More at the Passivhaus Trust
The really important thing demonstrated by these architects and builders is that Passivhaus is not just for the rich custom home builder but that it makes sense for townhouses, apartments and houses for all income strata. The issue of fuel poverty is just going to get worse, as are the climactic changes that increase the need for resilient design. Passivhaus makes sense for everyone.
More at the Passivhaus Trust.
Thanks to Ben Adam-Smith for the video links.