Measure a rectangular room — or add a second section for an L-shaped room — and get the area in square feet, metres and yards.
Area is length times width. An L-shaped or otherwise irregular room is handled by splitting it into rectangles, measuring each one, and adding the areas — the second section here covers the common two-rectangle case. Results are also given in square metres (sq ft divided by 10.764) and square yards (divided by 9), and the main section perimeter is included because it drives skirting board, trim and the wall side of paint calculations.
How is an L-shaped room measured? Draw the room as two rectangles, measure each rectangle's length and width, work out both areas and add them. Avoid double-counting any overlap where the rectangles join.
Do closets and alcoves count in room square footage? For flooring and paint, include any area that will actually be covered. For property listings, local rules vary on what counts as finished living space, so a listing figure may differ.