How do you find the square footage of a room?

Calculate the square footage of the room by measuring the length and width, rounding up to the nearest half-foot, and then multiplying these numbers to get the number of square feet. Rooms with non-rectangular shapes require additional calculations.

The square footage of a rectangular or square room is the length times the width. In a triangle-shaped room, measure the longest wall and the distance from that wall to the opposite corner, and multiply those numbers. Circular rooms must be measured from the center times pi, or times 3.15 for a simpler measurement. If the room consists of more than one shape, such as an L that has a rectangle and a square, calculate the measurements of each section of the room separately, and then add them.