Multiply the perimeter measurement by the height measurement and write the product down on the paper. Subtract 20 square feet for each door and 15 square feet for every window if you will be painting the trim around these areas with a different color. This gives you an estimate of the entire square foot area of the outside of the house.
How to Figure the Amount of Exterior Paint to Buy : Painting Choices & Tips
Frequently Asked Questions
How do I figure out square footage for paint?
To estimate the amount of paint you need in order to cover the walls of a room, add together the length of all the walls and then multiply the number by the height of the room, from floor to ceiling. The number you get is the room's square footage.