Linear footage is a measurement used in construction to determine length for purchasing construction materials. You can calculate the linear footage of a room by measuring the length of each wall and adding the sums of the length measurements. Many construction products, including floor boards, moldings and trim, are sold by linear feet.
Measure the length of a wall in a room. For example, assume a wall measures 8 feet.
Measure the length of the opposite wall in the same room. For example, assume the opposite wall also measures 8 feet.
Measure the remaining walls in the room. For example, assume the two remaining walls both measure 12 feet.
Add the length measurement of all of the room's walls. Continuing the same example, 8 + 8 + 12 + 12 = 40 linear feet. This figure represents the linear footage of the room.