|Wall (in ft.)||Height x Room Perimeter|
|Ceiling (in ft.)||Length x Width|
|Sloping Wall (in ft.)||Height x Base|
Total Painting Area:sq. ft.
Total Gallons of Paint Needed: gallons
TIPS ON MEASURING FOR PAINT
While paint is sold in gallons, you'll need to first find the square footage of the area. To cover approximately 400 square feet, you need one gallon of paint. Our calculator will do these calculations for you. To estimate how many gallons of paint you need, you'll want to take into account four specifications - wall height, wall perimeter, ceiling area, and, if applicable, any sloping wall areas created by cathedral-style ceilings. Don't worry about excluding window and door areas from your measurements. Just include them as if they were wall area, to ensure you have enough paint. Our calculator also includes a 10 percent waste allowance automatically.
- Wall Height
Measure from the floor to the ceiling, rounding to the nearest foot.
- Wall perimeter
Measure the length of each wall, and then add up the lengths from each wall together. (For example, if you have one room with four walls, all of the same height, you'll measure the horizontal length of each of these four walls, and then add these measurements together.) Round the number you get for the total perimeter to the nearest foot.
- Ceiling area
Measure the width and length of your ceiling, rounding to the nearest foot. (Obviously omit this measurement if you don't intend to paint the ceiling.)
- Excluded sections
Measure the height and width of each area separately. Add all widths into one total. Add all heights into a second total.
- Sloping Ceilings
If you have sloping ceilings, you'll have triangular wall space beneath. To calculate the square footage for this triangle shape, multiply the length of the wall at the base by the height at the highest point of the triangle area, and then, divide this resulting number by two. (Area of a Triangle = Base*Height*0.5)