Updated: Apr 8, 2021
At this point, we've spent more consecutive days in our homes then we only imagined in a zombie apocalypse type scenario and I'm sure there are one or two or ten areas you’ve grown tired of. With the future of the economy and our jobs in a questionable place, one easy, do-it-yourself, inexpensive update you can make is to slap a fresh coat of paint up on those tired walls. There's something about new paint, the smell and that clean fresh feeling you get while you sit back and admire your new space and think "I did this" in all your bad ass glory.
Now you’ve gone out to just about every store in a 25 mile radius that sells paint (no worries, I've been there) and you’ve finally found THE ONE. You’ve got your painters tape, some rollers, a brush, pans, floor covers and one of those trim painter thingies for the corners and edges..
Now, you may ask, how much of this beautiful, new, life changing hue do I need? This is where we have to math. Don’t get me wrong, I DO NOT MATH but if I can figure this out, so can you. Stick with me!
Here's a step by step guide on calculating paint
Step 1: Measure the LENGTHS of all walls and add them together
Step 2: Measure the HEIGHT of the walls
Step 3: Multiply the LENGTH of the walls x the HEIGHT of the walls (This figure is the square footage of the walls)
Step 4: Subtract the square footage of any doors and windows using the length x height formula above to get the total square footage of paintable space
Step 5: A gallon of paint generally covers about 350 square feet with a single coat. Divide your paintable square footage by 350. This final number is the number of gallons of paint required to complete your project.
I have two walls at 10' long and two walls at 20' long: 10+10+20+20 = 60
The walls are 8' high: 60 x 8 = 480
I have two windows at 15 sf each and one door at 20 sf: 480-15-15-20 = 430 square feet of paintable wall space
430 / 350 = 1.2286 gallons of paint required for one coat.
If you find that your calculations have you at some gallons and a half or more, its best to round up to the nearest gallon. If you are over a gallon by only a touch, you can pick up a few quarts of paint to make up the difference.
I would always recommend buying a bit more than you figure because nobody wants t0 run out of paint once its been mixed and go out to buy more only to find that this can is off by just enough that you'll see it forever and it'll make you crazy until you repaint again; but hey, at least by then, you'll know exactly how much paint to buy!
Pro Tip: When selecting paint, assume that it will look a little different in your house then it looks on that cute little tip card. Buy sample jars and paint a few well lit areas so you get a better idea of what it'll actually look like before investing in gallons.