More than 7,000 plastic bottles salvaged by the Colliers Wood community will be used to form an environmental structure, the like of which has never been seen before.

Deen City Farm’s sustainability centre, built in a former cob house, will feature a new roof made from the bottles collected in a recycling bin placed outside the civic centre.

The roof will be the final addition to the cob store - the refurbishment of which has sought to utilise new green construction techniques and materials.

Deen City Farm’s project co-ordinator, Louisa Loakes, said: “The RIBA (Royal Institute of British Architects) even wants to send someone down to look at the roof when it’s done because it’s so unique.

“Not only the roof, but everything in the cob house has been designed with the environment in mind - we’ve been using recycled and reusable materials as much as possible.”

Wooden posts used to hold up for sale signs outside houses will form part of the roof’s structure while the building itself even includes a floor made from reclaimed tiles to a design inspired by William Morris.

Wimbledon Art College sculptor Will Waterhouse has designed the roof. The farm is planning on holding a volunteers’ day in August where the community will help transform the collected bottles into tiles.

Merton Council is even encouraging all its employees to bring their empty plastic bottles to work and drop them into the recycling bin.

The local authority’s cabinet member for environment and leisure services, Councillor David Simpson, said: "Once the roof is complete it will serve as a wonderful example of what can be achieved from something people throw away everyday without a second thought."

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