Green buildings: The state of the art
British architects are making up for lost time when it comes to environmentally intelligent design, writes Felix Mara
For many British architects, environmentally intelligent design remains what the philosopher Karl Popper referred to as the ‘problem situation’ of today. This is the code everyone wants to break, paradoxically elbowing opposition out of the way in order to expand collective wisdom. But we were much slower off the mark than architects overseas.
Despite much discussion, compliance with the Code for Sustainable Homes only became mandatory in Britain in September 2010 and although the BRE’s voluntary EcoHomes rating scheme was introduced in 2000, this was eight years after France’s HQE standard, and 10 years after the first Passivhaus in Darmstadt.
The cynical might even argue that this recent activity is a smokescreen for British architects and manufacturers’ creative paralysis and inability to innovate in other technical fields. But some current British projects just might help to refute or temper these criticisms through the quality of creative environmental thinking in the three fields of retrofit, passive new-build residential design and ecologically responsible commercial new-build.
At one end of the retrofit scale stands Hawkins\Brown and Studio Egret West’s makeover of Sheffield’s Park Hill housing estate for Urban Splash. Being Grade II*-listed, extensive demolition wasn’t an option, and would have involved huge embodied CO2 costs.
Although it was completed in 1961, Park Hill had environmentally intelligent features: natural cross-ventilation, district heating and dual aspect flats. ‘So inefficient’, today’s developers would say – not that efficiency has any meaning as a measure of civilised values and human dignity. Living rooms face south and west, whereas bedrooms face north and east, so it used solar gain, when and where it was most beneficial. The retrofit has much more external glazing, significantly improving daylight levels. Park Hill’s life has also been prolonged by improving insulation and rejuvenating it with contemporary materials and colours.
At the other end of the scale, Penoyre & Prasad, acting almost as GPs or social workers, consulted the occupants of a 1992 terraced house in London’s Docklands, assessed both their concerns and their energy use and made very specific modifications. ‘We detected very high levels of electricity used to wash and iron clothes and run the tumble dryer,’ says senior architect David Cole. ‘Daylight levels were quite good, but the middle of the house was very dark and quite depressing.’
Penoyre & Prasad improved natural ventilation and storage by introducing a top-lit space above the staircase that is used to dry clothes and improves loft access. Achieving the 80 per cent CO2 emissions reduction required by the Technology Strategy Board’s Retrofit for the Future programme, Penoyre & Prasad’s scheme also collected a prize at the AJ’s 3R Awards this year.
In the area of new-build passive housing, the Triangle in Swindon, by Glenn Howells Architects (AJ 10.11.11) uses established passive design principles. Solar gain and natural ventilation have informed the orientation and fenestration of the houses. They also benefit from advances in building envelope construction, using Hempcrete to offset the equivalent of four years’ CO2 emissions and louvred intakes that residents can lock so thermal chimneys continue to function when they go out. ‘It’s neither a passive house nor an active house: it’s a reactive house,’ says Davinder Bansal, director of Glenn Howells.
Gokay Deveci’s Tigh-Na-Cladach in Dunoon (AJ 28.10.10), a smaller, more affordable housing development, uses Scottish Passive House Centre certificates and calculation sheets to demonstrate that the way this type of project is set up and run is crucial to its success. ‘We had a local builder who hadn’t done anything like this, so I needed to set up a methodology,’ says Deveci. ‘I encouraged partnering instead of tendering, discussed the objectives with the design team so they felt involved and asked the site agent to report everything.’
As for commercial new-build, the WWF headquarters in Woking, designed by Hopkins Architects with Sturgis Carbon Profiling is expected to start on site next year. It used whole-life CO2 analysis at the early design stage to optimise operational and embodied emissions, with that essential ingredient: interdisciplinary coordination of CO2 impacts.
The Woodland Trust HQ (AJ 28.10.10) aims to minimise embodied energy and is one of a series of collaborations between Feilden Clegg Bradley Studios and Max Fordham that exploits thermal mass.
Unlike earlier projects with concrete decks, it uses timber with soffit-mounted concrete radiators providing thermal mass. ‘The design team calculated that this would produce 900kg less CO2 than concrete floor construction – that’s 20 years of emissions,’ says Feilden Clegg Bradley partner Matt Vaudin.
Although many believe the new ‘problem situation’ involves integrating environmentally intelligent design into architecture that works on every level, these projects demonstrate that there is still a rich vein of technical invention and resourcefulness in Britain that is continuing to enhance building performance.