For those trying to make sustainability sexy, green roofs are often touted as exotic sky gardens, but the reality is they are frequently little more than plain expanses of sedum.

Lee Evans sees it as a missed opportunity. The founder of Organic Roofs likes to consider each roof as a field or a wildflower meadow.

When installing a new roof he takes the local biodiversity into account and attempts to emulate nearby areas of special scientific interest in order to create ecologically significant habitats and open up areas to bees, butterflies, moths and insects.

He looks at what the soil conditions are in the area, what plants are thriving, what native species prosper, what species are endangered and how their numbers can be increased.

He says: “As a guiding principle I want to feel as though I’ve made some advance, some healthy contribution to helping fill up our cities with green spaces and turn our buildings into contributions to bio- diversity. There are targets for increasing the amount of green spaces by 2020 that can’t be done by creating park space alone. Land is too valuable. But if you look at a map of a city from above there is a huge amount of space available.”

Before launching Organic Roofs this year, Lee was an academic, studying and teaching international development at the University of Sussex. He realised academia wasn’t for him and retrained at a carpenter.

Then, at a weekend workshop on green roofs had what he describes as a “light bulb moment”.

He says: “It’s such an elegant idea. It’s not a silver bullet or a panacea but definitely forms several functions in terms of sustainable development.

Also it looks so good and it’s so much fun to do. I just had an epiphany that it’s what I wanted to do.”

While most green roofing organisations focus on large-scale commercial premises such as hospitals and schools, or projects such as the 16,000 square metres of green roof being installed on the Southern Water pumping station at Peacehaven, Lee prefers to concentrate on residential properties because “it’s not just something that happens out there to other people. It’s something we can all do to make a contribution. There’s not really anyone doing what I’m doing, it’s unique in terms of scope and orientation, certainly in the South East.”

And Brighton is, as ever, the place to be. “Most of my work is in London at the moment,” he says. “But I’m developing a stronger base in Brighton and lots of people here are receptive to these ideas.”

However, the city does provide one problem in that its Regency facia doesn’t always lend itself well to the technology. “Although the main challenge is that a green roof can cost up to twice as much as a normal one,” he says. “It is something which is kind of exclusive. I very much see my business promoting to the people who can afford it and using that as a way of subsidising more inspiring public projects, underwriting projects which may occur in a lower income bracket.”

* Visit www.organicroofs.co.uk for more information