Multiply the perimeter of the home by the height. TIP: For a more accurate estimate, subtract doors and windows from your wall area calculation. An average window is 15 square feet and an average door is 20 square feet. If you have gables, multiply the width of the gable by its height, and divide by two.
To estimate the amount of paint you’ll need for the trim, estimate the length of total trim. The average trim width is six inches. Multiply the total trim length by 0.5 feet. To estimate the gutter, determine the total length of the gutter.
How to Calculate Quantity of Paint.
Frequently Asked Questions
How much paint do I need for exterior of house?
And when calculating how much paint to buy, professionals recommend adding an extra 10 or 20 percent to your total square footage. It takes two coats to cover a home exterior, and one gallon of paint covers about 400 square feet.