How to estimate paint for your garage
Garage walls are often bare drywall, primed block, or masonry, so coverage is a bit lower than a finished room, so this calculator defaults to 320 square feet per gallon. Enter the garage dimensions and count the garage door as one large door plus the entry door.
For unpainted concrete block or brick, coverage can fall to 250 or less on the first coat, so lower it in Advanced. Priming bare block first will noticeably reduce how much finish paint the surface drinks.
Coverage cheat sheet
| Surface / situation | Approx. coverage per gallon |
|---|
| Smooth, previously painted surface | 350 to 400 sq ft |
| New or bare wood / drywall (thirsty) | 250 to 350 sq ft |
| Textured, rough, or weathered | 200 to 300 sq ft |
| Primer | 200 to 300 sq ft |
This tool defaults to 320 sq ft per gallon for a garage. Change it under
Advanced if your surface is rougher or more porous than average.
Frequently asked questions
How much paint do I need for a two-car garage?
A standard 20 by 20 two-car garage with 8-foot walls has about 640 square feet of wall. Two coats at 320 sq ft per gallon is roughly 4 gallons before subtracting the doors.
What paint should I use on garage walls?
A washable satin or semi-gloss interior latex works for drywall. For bare concrete block, use a block filler primer first, then a masonry or acrylic paint for a durable, cleanable surface.
How many square feet does a gallon of paint cover?
One gallon of interior wall paint typically covers 350 to 400 square feet in a single coat. Textured, porous, or dark-to-light surfaces cover less, so this calculator uses a conservative default to keep you from coming up short.
Should I buy extra paint?
Yes. Keep a little for touch-ups. Rounding up to full gallons usually gives you enough of a cushion; for large jobs, add roughly 10 percent so you have a color-matched can on the shelf later.