Great Interior Design Challenge

The amateur designers must transform a bedroom in a modernist former leisure centre in London, which happens to be one of presenter Tom Dyckhoff's favorite buildings in the UK.

The remaining designers are out to impress, working in Kentish weatherboard cottages.

This design showdown takes place at a Scottish castle, now converted into apartments.

The second heat begins in the beautiful thatched village of Briantspuddle in Dorset, an unusual Edwardian experiment.

The three remaining designers work on a smart Georgian terrace in Bath.

The remaining two designers transform tiny bedrooms in medieval timber-framed houses.

Four amateur designers transform cottages in the Peak District village of Tissington.

Three designers take on the demanding task of redesigning kitchens on a tight budget.

Two designers must transform attic bedrooms in high-end riverside properties in Marlow.

Four designers must transform bedrooms in a self-build estate in south London.

Three designers must each transform a reception room in the model village of Bourneville.

In the last round of the heats, two designers must each transform a farmhouse kitchen.

The last four designers redesign sitting rooms and face a team challenge.

Three designers take on a sitting room each in a medieval terrace in Wells.

The final two designers battle it out for the championship in a three-room design challenge that asks them to transform a grand stately home in Sussex.

In this special programme, "Great Interior Design Challenge" brings together the ultimate rules of design - room by room.