The creativity of the structural engineer Michael Chester + Partners enabled the corner of this rebuilt extension to be free of roof supports and the resulting huge window - approximately twice the area of the already large original - transforms the relationship between the flat and its spectacular mature garden. The resulting views back into the living room from the terrace are as intriguing as those out from the living room towards the new glass sculptures on the lawn. The rebuilt external walls are formed out of rendered studwork, allowing the new frameless glass sliding door to retract into the wall cavity, together with an inner perforated aluminium security screen specially commissioned from US artist Danny Lane.