So you have decided on the perfect color for your walls. Great, so you are ready to go buy your paint but wait. how much should you buy? If you buy too little you will have to go back to the store and try to match the same color. If you buy too much you are just throwing money away. So how do you choose how much paint to buy?
First you need to accurately measure your wall space. Multiply the length by the height of each wall and add those numbers together. If you will be painting the ceiling the same color you should multiply its length by width and add that to the total. Do that for all of the rooms that you will be painting and add the totals together. now multiply that number by 15%. The extra 15% accounts for waste, spillage and a little extra left for touchups.
Now that you have your total you need to find the spread rate of your paint. This is the number of square feet that the manufacturer says the paint will cover per gallon. This number will vary from manufacturer to manufacturer but will generally be around 3 to 4 hundred square feet per gallon. Divide this number into your total square footage of wall space any you have the number of gallons that you need.
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