AN ARCHITECT firm has won a major award for designing a home in Dursley that appeared on Channel 4’s Grand Designs.

Millar and Howard Workshop, an award-winning architecture practice based in Chalford, has won the coveted Telegraph and Homebuilding & Renovating Magazine Best Passivhaus award for a tree house built in Dursley, which appeared on Grand Designs last year.

A passivhaus – the widely used German name for passive house - is a voluntary standard for energy efficiency in a building, where the ecological footprint is drastically reduced, resulting in buildings that require little energy for heating or cooling.

Millar and Howard’s award-winning tree house sits between Sainsbury’s supermarket and the church in Dursley.

The house is timber-clad with a cantilevered structure, and perches among the tree tops 12 metres above ground.

It took over two years to build the house on the previously overgrown, neglected site – a site that home owner, Jon Martin spotted as a child and which, four decades on, he acquired for £85,000.

Grand Designs followed Jon and his partner Noreen as the build went ahead, with the project hitting many obstacles along the way, and Kevin McCloud, the Grand Designs’ presenter, has since described the property as truly magical.

Though a self-build project, architects Millar and Howard involved several local consultants to help achieve the home’s hard-won passivhaus status.

Tomas Millar, co-director of Millar and Howard Workshop, said: "It was a great project to be involved in.

“Attaining passivhaus certification was an achievement in itself, but for the design of the house within that to be recognised is brilliant.

“PassivHaus is an engineering standard and the fact that is so rigorously audited is its great strength.

“What is wonderful about the tree house is that it demonstrates what’s possible when adopting a broader, more balanced approach."

The award’s judges praised those involved in the project for having overcome a number of obstacles to create the imaginative, low-energy home.