All calculator results on RoomCalculator are estimates only. They are based on the measurements and options you enter, and on standard coverage and wastage assumptions. Actual paint, wallpaper, and tile needs can vary with wall condition, pattern, tile cuts, and product coverage. Please double-check with a tape measure or contractor before buying materials. By using this site, you agree that RoomCalculator is not responsible for overbuying, underbuying, or installation costs resulting from estimated results.