Things You'll Need
As you plan and prepare to paint a room, you must accurately measure the dimensions of the surfaces to enable you to purchase the proper amount of paint. With basic measuring, multiplication and addition, you can accurately determine the square footage of a room to know how much paint you will need to cover the surfaces. Remember to consider multiple coats of paint and any other special architectural features as you figure ceiling square feet for painting.
Stand on the stepladder to reach the upper edge of the wall. Measure the width of the ceiling with the tape measure and write down this dimension on the paper.
Measure the length of the ceiling with the tape measure and write down this dimension on the paper.
Multiply the width measurement by the length measurement to find the area of the ceiling. This is the square foot measurement of the ceiling and the amount of area you must cover with one coat of paint.
Multiply the area of the ceiling by two if you will be applying two coats of paint.
Figure in any special architectural features to the ceiling area, if necessary. For example, if you have a tray ceiling and you want to paint this extra depth the same color as the ceiling, you must measure the lengths and widths of these areas with the tape measure and multiply them together to figure the area. You may need to add several small areas together to reach a total tray ceiling area and then add this extra area to your base ceiling area for a grand total.