How to calculate square footage
- Choose whether you measured in Feet or Metres.
- Enter the Length and Width. Use decimals for part feet: 12 ft 6 in is 12.5.
- Read the area in square feet, square metres and square yards. Add a Price per unit area to see the total cost.
L-shaped and irregular rooms
Split the floor into rectangles that don’t overlap, measure each one, run them through the calculator and add the areas together.
Say a living room is 14 × 12 ft with a 6 × 5 ft alcove off one side. The main part is 168 sq ft and the alcove is 30 sq ft, so the floor is 198 sq ft in total. For a room with a corner cut off at an angle, work out the full rectangle and take away the triangle, which is half its two short sides multiplied together.
Leave out areas you won’t cover, such as a fitted kitchen unit or a hearth, by measuring them as rectangles and subtracting.
How much extra flooring to buy
Flooring needs cutting at walls, doorways and around pipes, and some pieces end up too short to use. Add 5 to 10% to the area before you order. Use the lower end for a plain rectangular room with large planks or tiles laid straight, and the upper end for small rooms, lots of corners or a diagonal pattern.
For the 198 sq ft room above, 10% extra is 217.8 sq ft. If the flooring comes in packs that cover 20 sq ft, that is 217.8 ÷ 20 = 10.9, so buy 11 packs. A spare pack from the same batch also helps if a board gets damaged later, since colours can vary between batches.