A new type of roof garden planned as part of a housing project could help save energy and protect people from extremes in temperature.

Plans for six new affordable houses with environmentally friendly green roofs have been earmarked for St James's Street Mews in Kemp Town, Brighton.

If approved by planning authorities, the scheme would be the first in the city to feature the groundbreaking design, which basically involves growing plants literally on the top of buildings.

Traditional roof gardens have largely been restricted to growing plants in containers and planters but recent developments include multi-layered systems, which recreate growing conditions.

As well as providing city residents with much-needed outdoor space, bio-diverse roofs are said to insulate properties from extreme heat and cold.

The new scheme from developers Conran & Partners includes other sustainable features such as sun-pipes to light the kitchens and water-saving appliances.

The one-bedroom properties would be made from black brick, be suitable for two people and be put up for sale on a shared ownership basis or rented out at affordable prices.

Paul Zara from Conran & Partners said: "This aims to be one of Brighton and Hove's best smallhousing projects and one of the most environmentally-friendly.

"It helps meet the city's targets for affordable housing. It will be well-built, energy-efficient and of a high design standard.

"It will provide a real feature in this part of Kemp Town."

Brighton and Hove City Council, which will make the final decision on the application, has said it wanted to encourage such green policies and would give preference to designs with roof gardens.