Stair Carpet Calculator
Use this stair carpet calculator to determine the correct dimensions of carpet you will need to cover your stairs and how much it would cost.
Carpet needed7.547 sq yd67.93 sq ft including 10% waste
Length of runner20.583 ft20 ft 7 in up the flight
Per step19 in7.5 rise + 10 run + 1.5 nosing
Area per step4.75 sq ft
Steps13
Width36 in
Before waste6.861 sq yd
Broadloom needed20.58 ft of 12 ft rollif cutting from a standard 12 ft width
The method
per step = (rise + run + nosing) × width
Do not forget the nosing
Carpet has to wrap the front edge of each tread, so every step takes the rise plus the run plus an extra inch or two round the nose. Over thirteen steps that wrap adds well over a foot of material — enough to leave you short if you measured only rise and run.
Buy the whole flight from one roll and cut it in one piece where you can. Carpet has a pile direction, and a piece laid the other way up a staircase catches the light differently and looks like a repair.