Local green garden office

According to my local newspaper, The St Albans Observer, environmental scientist Neil Johnston has designed and built an innovative garden office that maintains a comfortable temperature with the minimum of heating. Alex Lewis writes that Mr Johnston has built a prototype in the back garden of his house in Granby Avenue, Harpenden, and that it needs no electricity at all on clear winter days. "But unlike rival designs which maximise sun capture by large amounts of glass, his office, through carefully positioned south-facing windows, stays cool in summer," he writes. The walls, floor and ceiling have 10cm of sawdust for insulation, bolstered by two-inch air gaps under the floor.The office has been built with Douglas fir from a sawmill in Ayot Green and a special plasterboard made from recycled plastic. The roof is only 2.25 metres high, reducing the space that has to be heated.