Canmore House, Chesterton, near Cirencester, included a new glazed extension to add an open plan kitchen dining space to a traditional Cotswold property. The design includes a feature bread oven and large sliding glass doors which open the living space to the garden. A rooflight joins the extension to the original house, brining daylight into the centre of the kitchen dining space. A natural Cotswold stone wall wraps around the extension, with a window positioned at high level to separate a lightweight green sedum roof which floats over the glazed doors below. The design is simple yet elegant in its detailing, complementing the traditional appearance of the original house. Our sustainable approach to design includes underfloor heating is provided throughout the new kitchen dining space, which coupled with the high performance large sliding doors, creates a flexible and open plan space which is also thermally efficient. The extension also insulates the original house, radiating heat back into the property and reducing long term heating costs.