How Much Paint for a Garage?
A standard 20x20 two-car garage has about 684 square feet of wall once the door and a window are taken out, so two coats runs about 6 gallons, plus 3 gallons of primer if the drywall is bare. A 12x20 one-car garage is closer to 5 gallons and a 30x22 three-car is closer to 8. The floor is a separate job priced by square foot, not by gallon. Enter your own dimensions below for a number based on your actual walls.
Pre-Calculated Paint Estimate
Low
5.0
gal
Likely
5.6
gal
High
6.4
gal
Primer Needed
3
gallons
This range covers 684 square feet with 2 coats. The likely estimate is 4.89 gallons before the selected buffer. If you are buying whole gallons, plan on 6.
Epoxy-based or garage floor paint recommended for durability. Standard latex works for walls.
View Detailed Breakdown
Based on a 20x20 ft room with 9-ft ceilings, 1 door(s), and 1 window(s). Paint at 400 sq ft/gallon with a 15% buffer.
See the formula and assumptions
Supplies for this room
Picked from the inputs above. Links go to Amazon and we may earn a commission at no extra cost to you. Details
- PVA drywall primer You selected PVA primer, the right choice for bare drywall. View PVA primer ›
- Scuff-resistant garage wall paint Garage walls take abuse, so pick a scuff-resistant finish. You need about 6 gallon(s). Browse garage paint ›
- Garage floor epoxy kit Doing the floor at the same time? An epoxy kit is the durable option. View epoxy kits ›
- Airless paint sprayer At five gallons or more, a sprayer saves hours of rolling. View sprayers ›
Rather not do it yourself?
Compare quotes from local painters. Bring your gallon estimate so the bids line up.
Before using the preset
Measure this room without the usual shortcuts
The result above is a worked example using the dimensions and openings shown in the breakdown. Use these room-specific checks before treating it as a shopping quantity.
- 1 Measure the large overhead door as a custom opening. This preset does not automatically subtract a garage door.
- 2 Confirm whether the walls are finished drywall, bare block, or previously painted masonry before using the preset coverage rate.
- 3 Estimate the ceiling separately because many garages have a larger or sloped ceiling area.
Tips for This Room
- Use a durable satin or semi-gloss finish for garage walls - flat paint scuffs too easily.
- Prime new drywall or bare concrete block before painting for proper adhesion and coverage.
- Light colors (white, light gray) brighten garages and make finding tools easier.
- Consider epoxy-based floor paint separately for the garage floor - regular wall paint will not hold up.
Paint needed by garage size
Wall figures come from this calculator using 9 ft walls, one entry door, one window, and two coats with a 15 percent buffer. Floor area is listed separately because floor coatings are sold by coverage area, not by wall gallons.
| Garage size | Wall area | Paint, 2 coats | Primer if bare drywall | Floor area |
|---|---|---|---|---|
| 1-car (12x20 ft) | 540 sq ft | 5 gallons | 3 gallons | 240 sq ft |
| 2-car (20x20 ft) | 684 sq ft | 6 gallons | 3 gallons | 400 sq ft |
| 2-car large (24x24 ft) | 828 sq ft | 7 gallons | 4 gallons | 576 sq ft |
| 3-car (30x22 ft) | 900 sq ft | 8 gallons | 4 gallons | 660 sq ft |
Garage doors are not deducted automatically. If your overhead door takes up a full wall section, subtract it as a custom opening in the calculator and your gallon count will drop.
Ready to Start Your Project?
Everything you need to get professional results.
Epoxy Floor Paint
Garage-floor epoxy coating designed to resist common chemicals and tire marks.
Shop Floor PaintDrywall Primer
PVA primer for new drywall in garages. Seals the surface for even paint coverage.
Shop PrimerPaint Supplies
Heavy-duty rollers, brushes, and trays for large garage painting projects.
Shop SuppliesProduct links go to Amazon.com
Frequently Asked Questions
How many gallons of paint for a 2-car garage floor?
Floor coatings are not measured in wall gallons. A 20x20 two-car garage has about 400 square feet of floor, and a typical two-part epoxy kit covers 250 to 500 square feet depending on how thick you lay it and how porous the concrete is. One large kit usually does a two-car garage in one coat. Buy by the kit coverage printed on the box, not by the wall estimate above.
How much paint do I need for a 2-car garage?
This 20x20 preset uses about 5.6 gallons for two coats on new drywall, so plan on 6 gallons of finish paint. It also includes about 3 gallons of PVA primer. A large overhead door should be deducted separately.
What kind of paint should I use in a garage?
Use interior latex paint with a satin or semi-gloss finish for garage walls. These finishes are more durable and easier to clean than flat paint. For garage floors, use a dedicated epoxy or concrete floor paint.
Do I need to prime garage walls before painting?
Yes, primer is strongly recommended for garages, especially if the drywall is new, bare, or unpainted. PVA drywall primer is the best choice for new drywall. Use a bonding primer for previously painted glossy surfaces.
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