The bare living room smells of paint, like all new living rooms, and nothing looks particularly unusual. But these new flats near Redhill, Surrey, are unique. They belong to Raven Housing Trust, the local housing association, and, in building speak, they will be the first inhabited flats in the UK built to “level 5″ on the Code for Sustainable Homes scorecard.

In lay terms, this means that they are 100% more energy efficient than standard building regulations (level 1), and are the most eco-friendly homes yet built by the Housing Corporation – the government body that funds and regulates housing associations. The new residents move in in a few weeks and will be plucked from Raven’s list of deserving tenants.

Social housing is traditionally viewed as the poor relative of private accommodation, but now, rather like the tortoise and the hare, it has overtaken its flashy adversary and stands at the vanguard of the eco-housing revolution.

A close look reveals that the walls of the flats are thick. They have been highly insulated and then covered with natural brick and clay tiles. From the outside, the house – which is divided into two flats – looks traditional. Inside, the windows are triple-glazed and there are no radiators – under-floor heating does their job.

These are intelligent flats that conserve energy. Any heat generated, be it from TV screens or children running about, is harnessed by a “heat-recovery ventilation system” and fed back into the flats using fresh air brought in from outside. They have solar panels on the roof, and a biomass boiler that runs off wood pellets – although they are plugged into the National Grid, just in case.

The plan is to monitor how much energy is used and from what source. To this end, meters scrutinising the residents’ every carbon move have been installed. “The idea is to find out how much people use, because at the moment you’ve only got demonstration houses and you’ve got no idea what happens in practice,” says Peter Trowbridge, development manager for Raven Housing Trust. All the information will continuously be fed back to the Energy Savings Trust and collated over two years.

Rainwater harvesting, low-flush toilets, low-flow taps and showers all encourage a water consumption rate of 80 litres a day per person (about half the average). But whoever Raven selects to live in these flats will need to be aware of the physical constraints – the particularly small bath is designed to conserve water.

The Redhill flats fall just one level short of being zero carbon (code level 6), where any energy consumed has to be less than or equal to that replaced through renewable technologies. That is the level the government has declared all new housing must reach by 2016 – an ambitious promise, and one the industry is in turmoil over.

“I think the building industry is scared stiff of it because it’s so foreign to them,” says Andy Lock, head of technical at Osborne building contractors, which built the flats. “They don’t understand it. The way we’re learning is to just keep pushing it a little bit further.”

Nick Harris, chief executive of Raven Housing Trust, agrees that the private sector has more to do. “The affordable sector is leading the market at the moment, but the private sector will have to catch up to meet the 2016 requirement,” he says.

Upgrading stock

Given that a third of carbon emissions come from housing, and that by 2050 at least three-quarters of homes in the UK will be old stock, wouldn’t it be wiser to plough money into converting draughty old buildings? “The upgrading of the existing stock is an absolutely vital thing, and we are totally underinvesting in that at the moment,” says Sunand Prasad, president of the Royal Institute of British Architects and one of 12 experts advising the government on eco-towns and villages. “It is essential for survival, but in the short term, finding the money is very difficult,” he says.

The total cost of building the two level 5 Raven flats is just over £300,000. But the commitment to get this scheme off the ground is such that the council gifted the land, while grants from the Housing Corporation, Osborne, Raven, Tandridge district council and others have also helped.

But not everything about the Raven homes is unconventional. In retaining a traditional appearance, its new flats buck the trend of most of today’s eco-housing.

guardian.co.uk/environment/greenbuilding

[Courtesy of The Guardian]