Basement Paint Calculator
This basement preset assumes finished new drywall in a dry basement and includes PVA primer. Bare concrete or block is a different surface with product-specific preparation and coverage, so use the coating label and enter its coverage rate instead of relying on this drywall preset.
Pre-Calculated Paint Estimate
Low
3.6
gal
Likely
4.0
gal
High
4.6
gal
Primer Needed
2
gallons
This range covers 493 square feet with 2 coats. The likely estimate is 3.52 gallons before the selected buffer. If you are buying whole gallons, plan on 5.
Use moisture-blocking primer first. Consider waterproofing paint for below-grade walls. Add 30% extra for concrete block.
View Detailed Breakdown
Based on a 20x15 ft room with 8-ft ceilings, 1 door(s), and 4 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 ›
- Mold-resistant basement paint Basement walls do better with a mold-resistant coating. Browse basement paint ›
- Airless paint sprayer At five gallons or more, a sprayer saves hours of rolling. View sprayers ›
- 9-inch roller kit with tray A 9-inch roller kit with a tray covers walls quickly. View roller kits ›
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 Identify the substrate first. Finished drywall, painted masonry, and bare block should not share one coverage assumption.
- 2 Check for active leaks, efflorescence, or damp areas before measuring for paint. A coating is not a repair for water entry.
- 3 Measure small foundation windows and utility-room openings separately. This preset includes two standard and two small windows.
Tips for This Room
- Always address moisture issues before painting - check for leaks, condensation, and water stains.
- Use moisture-blocking primer on concrete block walls before applying topcoat paint.
- Mold-resistant paint formulas are recommended for basements, especially in humid climates.
- Allow extra drying time between coats in basements due to higher humidity levels.
Ready to Start Your Project?
Everything you need to get professional results.
Waterproofing Primer
Moisture-blocking primer that seals concrete and masonry basement walls.
Shop PrimerMold-Resistant Paint
Basement-grade paint with built-in mold and mildew protection for below-grade walls.
Shop PaintPaint Supplies
Rollers, brushes, tape, and drop cloths for basement painting projects.
Shop SuppliesProduct links go to Amazon.com
Frequently Asked Questions
How much paint do I need for a basement?
This 20x15 finished-drywall preset uses about 4.1 gallons for two coats, so it rounds to 5 gallons of finish paint, plus 2 gallons of PVA primer. For concrete block, use the coverage rate and preparation instructions printed on the masonry coating you select.
Do I need special paint for basement walls?
Use a coating approved for the actual substrate and conditions. Finished drywall in a dry basement can use a suitable interior wall paint. Bare or previously coated masonry needs a compatible masonry system, and active water entry must be corrected before painting.
Can I paint basement walls without primer?
New drywall needs an appropriate drywall primer. Bare masonry and previously coated masonry require the preparation and primer specified by the coating manufacturer. A sound, clean, previously painted drywall surface may not always need a separate primer.
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