It's the seventh of nine heats and three new designers battle it out for a place in the second round. The amateurs are redesigning large open-plan reception rooms in three 21st-century eco homes in Greater London. With just three days and £1,250, the amateur designers must deliver gorgeous rooms using materials sympathetic to the eco ethos. Australian-born Honor must put aside her love of everything white, as her homeowners prefer a darker, moodier palette. Fashion design graduate Alex gets his screen printer out to give his Manhattan loft design a geometric feel. While B&B owner Jane risks losing the confidence of her homeowners with her clashing colours. Architectural historian Tom Dyckhoff reveals the ingenious design behind these futuristic, energy-saving buildings. While judges Sophie and Daniel must scrutinise the designers' every decision before they can decide who deserves to go through to the next round.