BedZED was a joint venture between Bill Dunster, an eco-architect who wanted to trial zero carbon design, and BioRegional Development Group, an organisation set up to promote sustainable technology and living of all kinds. A third organisation, a Housing Association called the Peabody Trust, came on board later in the role of developer and social housing provider.
One third of the homes are private affordable housing on a 999 year lease, 1/3 are in shared ownership for key workers such as teachers, police, nurses etc, and 1/3 are rented as social housing. The high-density neighbourhood fits 99 homes onto only 1 Hectare, with 3 story blocks containing 1 - 4 bedroom homes. Cars are kept to the edges of the site and narrow alleys link the buildings. All homes have small ground or roof garden areas.
Construction materials and methods were chosen to be as replica
ble as possible, although the very thick highly insulated walls and green roof are not standard construction. Walls are built of high density concrete, with oak weatherboards and recycled steel beams, and with sedum (a form of succulent) roofs. South triple and quadruple-glazed windows bring in the sun to heat the mass walls. The most striking feature are the especially designed ventilation cowls on the roofs. When houses are designed as these are to be relatively airtight, with large thermal mass, good solar gain and high levels of insulation, adequate ventilation does become an issue even in the London climate! An experimental CHP (Combined Heat and Power) plant, though 85% efficient at converting waste urban street tree wood into heat and power, is no longer used, and the Living Machine for treating waste likewise lies inert. Both units proved too small to be cost effective, and the learning is that the management and maintenance required would work better for at least 500 houses.
While the design of the houses and services results in a significant reduction in the environmental footprint, the habits of most residents of BedZED are little different to the UK average. The first residents were given training in the most effective use of their house, but new residents now only get the manual (and who reads manuals?), and often don't use the systems to best advantage. Surveys have shown that behaviour plays as significant a part in environmental footprint as the buildings. If residents altered their behaviour, their footprint could drop below the sustainable global average footprint, but currently BedZED only achieves a partial reduction, even with state-of-the-art sustainable buildings and services,.
Community interaction between residents is higher than in average UK houses, but the full potential of cooperation remains to be realised. The community centre and meeting place is tucked out the back next to the (little used) sports field, and is consequently also little used. There is a small, bare neighbourhood square, a regular community cafe and farmers market, but for many residents it is just a place to live.
A transport plan built in from the start encourages more sustainable transport choices. There are fewer carparks than houses, and those for standard cars have a weekly charge. Electric cars park for free and there are charging points on site powered by the photovoltaic cells on most south-facing roofs. A car club operates from the site providing cars for hourly rental, and this is considered a good transition from private car use to public transport. There is plenty of bike storage on site. The average resident of BedZED drives 60% less than the London average.
BedZED is an impressive experiment in providing high-density housing that uses and encourages use of significantly fewer resources than standard housing. BioRegional continues to manage and monitor the learnings from BedZED, provides information and education on related issues, and is involved in further projects that take these ideas into other contexts.
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