Low energy innovations meet family habits

The impact of any retrofit depends on how people use the building. A single mother, three teenagers and an East London terrace offer the Technology Strategy Board a living piece of research.

Having her washing on show in Green Futures may not have been quite what Tracey Hillyard envisaged when she agreed to be a guinea pig in a low-carbon technology pilot. But the family’s laundry proved a key player in the story of single mother Tracey, her three teenagers, and their three-bed East London home: 61 Warwall.

This terraced house was one of three selected by social landlord East Thames Group for a £150,000 makeover, under the Technology Strategy Board’s Retrofit for the Future programme. Out of this budget, £72,500 was spent on construction, and the remainder went on design fees, VAT and nearly £10,000 worth of energy monitoring equipment.

It’s not just a showhome: it’s a living piece of research

It may seem a high price to retrofit a modern terraced house. For not very much more, you could buy a similar sized property, with its own damp patches and draughts. But the value of the project was to try out and test innovations which can turn problematic homes into ultra-efficient ones, developing prototypes upon which future retrofits can draw.

It’s important research: social housing makes up a quarter of the UK’s housing stock, which in total accounts for 26% of the country’s carbon emissions. So retrofitting this stock could make quite a cut in the UK’s carbon footprint.

Moreover, it may well prove easier to persuade social landlords to retrofit their stock (taking some weight off the bills for tenants, and so helping them to pay their rent) than to persuade private homeowners to go through the rigmarole alone.

Targets for the projects were therefore set high. Penoyre & Prasad, the London architects chosen to work on 61 Warwall, were asked to reduce the house’s carbon emissions by 80%.

So, how did they do it? Back to Tracey and her laundry. Many an architect pays lip service to the fact that any technology or design is in a constant dance with the human beings who use it. But Penoyre & Prasad took this to heart, spending time tuning into the family, asking fairly searching questions about how they live, their concerns and habits, and their aspirations for a comfortable home.

The architects looked for ways to achieve high energy efficiency, but also to improve the family’s experience of living in the house.

“It’s no use imposing an ideal way of living”, says David Cole, a senior architect at Penoyre & Prasad. “For example, many herald tightly sealed houses and mechanical ventilation as the most effective efficiency approach, and it’s central to the German Passivhaus concept. But I’d argue it’s inappropriate in social housing. It’s hi-tech and not much good if the inhabitants smoke and open windows – as the Hillyards do.”

The firm found that by far the most significant draw on electricity for this particular household was the laundry. The trusty tumble dryer made up a fifth of their bill. Add the iron and the washing machine, and simply getting the family dressed accounted for nearly half of the total electricity used.

So Penoyre & Prasad found a way to combine bringing more natural light and ventilation into the house with the creation of a new space to dry clothes naturally. Where once a gloomy central staircase was overshadowed by a loft, now a ‘lightwell’ opens the landing up to the sky. The window at the top of the shaft opens easily, letting fresh air waft around the neatly hung clothes – and it can even operate automatically, to stop things getting a bit stuffy as the kids come and go.

Another hit was the installation of vertical ventilation panels beside the windows [see picture], which allow air to flow through slots without the security risk of a clear opening on the ground floor. And if the house doesn’t already sound like a breeze, it now even has a roof that ‘breathes’. Insulated with natural materials such as wood fibre slab and hemp fibre quilt, it dissipates moisture and avoids condensation.

Today, 61 Warwall isn’t just a show home: it’s a living piece of research.

“The house is bristling with sensors,” says Cole, “which send data back to the Technology Strategy Board to evaluate which low-carbon technologies work in practice.”

So far, the project has been a success: energy use is down by an estimated 69%, and carbon emissions by 79%.
Tracey is delighted: “To be one of the select few to have these improvements is like winning the lottery. I feel proud to have a home in which all the members of my family can feel warm and cosy.”

In 2011, the project won the ‘Best small housing project’ category at the 3R Awards – a scheme celebrating the most innovative and effective retrofits launched by The Architects’ Journal, Construction News and New Civil Engineer. – Charlotte Sankey

Photo: Penoyre & Prasad