A Carpet for the stairs We are looking down on the stairs between the first and second floors of a tall terraced house. The carpet needs replacing.

To save space, the stairs turn like a spiral. There are twelve stairs between the first and second floors: three rectangular and nine corner stairs. The corner stairs are built in three sets of three.

The landing is the thirteenth stair. This is the view from the second floor landing.

To save space, the stairs turn like a spiral. The second floor landing extends over the first floor. The arrows point the way to go up the stairs. First floor landing Second floor landing

The corner stairs The carpet for each stair is cut separately. Each piece of carpet forms the tread and the riser below it.

The corner stairs: plan view B A Each stair overlaps the one below. The dashed lines show the position of the stair underneath. Draw a scale diagram of the net of each of the three corner stairs. Choose your own suitable scale. C Stair A is the lowest, Stair C is the highest.

How much will the whole carpet cost? The carpet will not include the first floor landing, but it will include the second floor landing, which is 120 cm long. You have information about the price of carpet on your sheet. Second floor landing

Carpeting the stairs: summary Why do carpet suppliers send out their own surveyors to people’s homes when they are buying carpets for stairs?