The Paint for a Room calculator estimates the number of gallons of paint needed to cover a rectangular room based on the length, width and height of the room.
INSTRUCTIONS: Choose units and enter the following:
Gallons of Paint for a Room (GP): The calculator computes the amount of paint needed for the entire room in gallons, and the total surface area including the ceiling in square feet. The calculator also returns the same for just the wall (no ceiling). However, these can be automatically converted to compatible units via the pull-down menu.
The calculator computes the surface area of the room including the ceiling and for the walls only. It then divides those areas by the paint coverage area (PC = 400 ft²/gal) to compute the number of gallons of paint. Most manufacturers call for one gallon of paint to cover between 400 and 450 square feet (ft2) of wall or ceiling. The formula for the surface area of a room is:
`A = 2*L*H + 2*W*H + W*L`
`A = A - (WD*15ft^2 + DR*21ft^2)`
Paint is used for walls in rooms around the world. In addition to aesthetics, paint provides protection for the wall materials and extends their life. Paint also provides sanitary benefits. Many governments require the painting of apartments (flats) for each new tenant.
Often ceilings are painted with different paint since they tend to have less contact with people and other things, and because ceilings make for nice accent (lighter) surfaces.
One should use the pricing for paint or primer that can be bought locally since prices may vary. However, the following prices are recent U.S. dollar costs for one gallon of paint or primer in the United States: