Yes, you can paint concrete and cinder block basement walls, as long as the wall is dry and the paint lets moisture pass through. Use a latex masonry paint on clean, sound concrete.1 Skip oil, alkyd and epoxy paints, which trap moisture in the wall.2 Paint changes the color of a wall. It doesn't stop water, so leaks get fixed first.
TL;DR
- Paint only dry, sound walls, and use a breathable latex masonry paint. The U.S. Department of Energy lists epoxy, oil and alkyd paint among the finishes to keep off basement walls because they trap moisture.2
- The wall's condition sets the prep. Damp, powdery, flaking or moldy walls need their cause dealt with before any paint goes on.
- Decorative paint and waterproofing are separate jobs. Building scientists keep water out from the outside, with gutters, grading and drainage.3
- Mold means water. Fix the water, clean up or bring in a remediation pro, then paint.2
- If the basement is becoming heated living space, the 2021 IECC calls for basement wall insulation in climate zones 3 through 8, outside Warm Humid areas, so the concrete ends up covered anyway.4 Local adoption varies.
Is it good to paint basement concrete walls?
Yes, painting a dry basement wall is a good, simple upgrade. It brightens the room and gives bare concrete a finished look. The catch is moisture. Concrete in contact with soil needs to dry toward the room, so the paint has to breathe. A sealed, impermeable coat traps that moisture and invites mold.3
Building scientist Joseph Lstiburek lays out the mechanism in Building Science Corporation's digest BSD-103. The traditional approach puts the water barriers on the outside of the foundation and lets the wall dry to the inside.3 He warns against impermeable interior wall finishes such as oil (alkyd) paints, because they block that inward drying and typically lead to mold growth.3
Your basement walls also run cold, because the concrete touches the ground. In summer, warm and moist air meets those cold surfaces and condenses.3 That's why a basement wall can look damp even when no water is leaking in.
The wrong paint can do real damage over time. On one home repair forum, a homeowner with a 110-year-old house asked about flaking basement brick. A frequent contributor replied that oil-based paint tends to trap moisture in the wall behind it and may have contributed to the spalling.1 Spalling is the face of the masonry breaking off as trapped water freezes and expands.1
So the answer is yes, as long as the wall is dry and the paint breathes.
What kind of paint do you use on concrete basement walls?
Use a latex masonry paint made for concrete and block. Masonry paints are usually latex, with resins chosen to let water vapor pass through the film.1 Avoid epoxy, oil and alkyd paints on the interior of basement walls. The Department of Energy classes them as Class I vapor retarders that trap moisture.2
Here's how the common options stack up on a basement wall.
| Paint or coating | On interior basement concrete or block? | Why |
|---|---|---|
| Latex masonry paint | Yes, on a dry and sound wall | Water vapor can pass through the film, so the wall keeps drying1 |
| Oil or alkyd paint | No | A Class I vapor retarder that traps moisture in the wall2 |
| Epoxy paint or coating | No | Also a Class I vapor retarder; Building Science Corporation rules out oil, alkyd and epoxy paint systems on walls that dry inward23 |
| Ignition-barrier paint | Only over exposed spray foam insulation | Spray foam must be covered with ignition-barrier paint or ½-inch gypsum board2 |
| Paint not labeled for concrete or masonry | No | The label sets the surfaces a product is made for5 |
Read the label before the brand
The brand name tells you little. The label tells you which surfaces a product is made for. When a homeowner asked on a retailer's page for a Krylon water-based chalky paint whether it could go on interior basement cement walls, the brand's reply said its Chalkboard Paint is specified for glass, ceramic, wood, metal and plaster.5 Concrete wasn't on the list.
Look for concrete or masonry on the can. Then check what the product is made of. If the label says epoxy, oil or alkyd, it doesn't belong on the inside of a basement wall.2 This test works for any brand you're comparing, including the ones people ask about by name. Use it on primer too. If the paint label calls for a primer on bare masonry, pick one labeled for concrete or masonry that isn't oil or alkyd based.2
Products sold as sealers or waterproofers
Some coatings are sold for sealing or waterproofing masonry. Judge them by the same test. Read what the label actually claims and what the coating is made of. An epoxy coating on the inside face is exactly the kind of Class I vapor retarder the DOE says to keep off basement walls.2 And no interior coating does the job of drainage outside the wall, which is where building scientists put water control.3
What prep does your wall's condition call for?
Match the prep to what the wall is telling you. A dry, sound wall needs cleaning and paint. A damp, powdery, flaking or moldy wall needs its cause found and fixed first. Paint over an active moisture problem only hides the warning signs your contractor needs to see.
| Wall condition | What it usually means | Do this first | Then paint? |
|---|---|---|---|
| Dry, bare poured concrete | A sound surface | Clean off dust and grime and let it dry | Yes, latex masonry paint |
| Dry cinder block | Porous, rough units with mortar joints | Clean, then fill cracks and holes | Yes, worked into the pores and joints |
| Old paint peeling or flaking | A loose coating, possibly an impermeable one | Remove the loose paint; forum contributors suggest a water jet or soft blasting media such as walnut shells on old masonry1 | Yes, once the surface is sound |
| White powder or a crumbling surface | Water moving through the wall | Find and fix the water source | Only after the wall stays dry |
| Damp only in humid summer weather | Condensation on cold concrete3 | Dehumidify the space3 | Yes, once the wall stays dry |
| Wet after rain, seepage or puddles | Water getting in from outside | Gutters, grading and drainage outside the wall3 | Not until the water stops |
| Mold growth | A water problem2 | Fix the water, then clean or remediate | After cleanup, on a dry wall |
| Exposed spray foam insulation | Foam that must be covered2 | Nothing to strip | Ignition-barrier paint, or cover it with ½-inch gypsum board2 |
Two rows cause the most confusion. The first is summer damp. Warm, moist air condenses on concrete that sits below the room air's dew point, which is why a wall can sweat without a leak.3 Building Science Corporation's guidance is to let the wall dry toward the room, where ventilation or dehumidification removes the moisture.3
The second is water that shows up after rain. That's a drainage problem, and the fix happens outside. Roof water should be collected by gutters and carried away from the foundation, and the grade should slope away from the house.3
Think about the bottom of the wall too. Finishes on the lower part of basement walls should be chosen with the chance of flooding in mind, whether from leaky appliances, failed plumbing or surface water.3
How do you clean concrete basement walls before painting?
Clean the wall only after the moisture question is settled. Then scrape off loose paint and flaking coatings, brush away dust and powder, wash the wall and let it dry completely. Paint needs a clean, sound, dry surface. Anything loose left on the wall comes off later and takes the new paint with it.
Step by step
- Check for water. Look at the wall after a heavy rain and during humid weather. Damp patches, puddles or fresh white powder mean you stop here and deal with the source.
- Remove loose material. Scrape peeling paint and any coating coming away in sheets. For stubborn old paint on brick or stone, one repair forum contributor suggested sandblasting or a water jet.1 Another suggested peach pits or walnut shells as the blasting media, warning that anything harder can destroy limestone and brick.1
- Brush and wash. Use a stiff brush to clear dust, cobwebs and powder. Wash the wall with water and a mild cleaner, then rinse it.
- Let it dry. Give the wall time to dry out fully. A dehumidifier helps in a humid basement.3
- Patch. Fill cracks and holes with a patching product labeled for concrete or masonry, and let it cure as its label says.
If you find mold while you clean, stop scrubbing and read the next section first.
Can you paint over mold on basement walls?
No. Paint over mold leaves the cause in place. As building scientist Joseph Lstiburek puts it in a Department of Energy profile, "Mold is a water problem. No water, no mold."2 Fix the water source, remove the growth, let the wall dry, then paint with a breathable masonry paint.
The DOE profile names the usual water sources. Indoor air condenses on basement walls that sit below the dew point, and rainwater or groundwater can wick through footings or walls.2 Any of those will keep feeding mold under a fresh coat of paint.
A paint that seals the wall makes things worse. Impermeable finishes block inward drying and typically lead to mold growth and other moisture problems.3
If the growth covers a large area, keeps coming back or sits behind finished materials, bring in a qualified mold remediation professional, licensed where your state requires it. HomeGuide's national cost guide puts mold remediation at $15 to $30 per square foot.6 If you're not sure how big the problem is, have it assessed before anyone paints.
Is it okay to paint basement cinder block walls?
Yes. Cinder block takes paint the same way poured concrete does, and the same rules apply: a dry wall, a sound surface and a breathable latex masonry paint.1 Block is rougher and more porous, so expect it to soak up more paint and to need that paint worked into the pores and mortar joints.
Block walls are common in older basements. Lstiburek notes that old cellars were built from rubble, stone, brick and sometimes block, and nobody much minded if they got damp.3 A basement you plan to use is different. It needs to be dry and comfortable.3
Block walls need a few extra checks before paint. Look for stair-step cracks along the mortar joints, a wall that bows inward, or joints turning to sand. Those are masonry or structural repairs, not paint prep. Have a mason or structural engineer look at a bowing or badly cracked block wall before anyone covers it.
For the paint itself, follow the label's directions for rough masonry, including its coverage rate. A rough block face uses more paint than smooth poured concrete, so buy with that in mind.
Where does decorative paint end and waterproofing begin?
Decorative paint changes how the wall looks. Waterproofing controls where water goes. Building science puts that control on the outside of the foundation, with gutters, sloped grading, drainage and exterior damp-proofing.3 An interior coat of paint, even one sold as a sealer, doesn't replace any of those.
BSD-103 describes the full system. Collect roof water with gutters and move it away from the foundation. Slope the grade away from the house.3 Use free-draining backfill or a drainage mat to carry water down to a perimeter drain, and damp-proof the wall on the outside.3 None of those are paint jobs.
The inside face of the wall has one job in that system. It lets the wall dry into the room. That's why the DOE's list of things to keep off the interior of basement walls includes polyethylene sheeting, vinyl or foil wallpaper, and epoxy, oil or alkyd paint.2
| Decorative masonry paint | Waterproofing | |
|---|---|---|
| What it does | Colors and brightens a dry wall | Keeps liquid and capillary water out of the wall3 |
| Where it goes | The inside face of the wall | Mostly outside: gutters, grading, drainage and exterior damp-proofing3 |
| Moisture rule | Must let the wall dry inward3 | Vapor barriers belong on the exterior3 |
| Rough cost | Priced at your estimate | $6,000 to $18,000, HomeGuide's national figure6 |
If water is coming in, compare waterproofing methods and price the real fix first. Your own waterproofing job is priced at your estimate, once a contractor finds where the water comes from.
Should you paint the walls if you're finishing the basement?
Usually not as the final finish. If the basement is becoming heated living space, the 2021 International Energy Conservation Code requires basement wall insulation in climate zones 3 through 8, so the concrete ends up covered.4 Paint makes most sense for storage, laundry and utility areas that stay unfinished.
The rule sits in section R402.2.8, which points to Table R402.1.3 for the R-values.4 Here's what that table sets for the metros Basement Remodeling Co. serves.
| Metro | Example counties | 2021 IECC climate zone | Basement wall R-value in Table R402.1.3 |
|---|---|---|---|
| Atlanta | Fulton, Cobb, DeKalb, Gwinnett7 | 3A | 5ci or 134 |
| Denver | Denver7 | 5B | 15ci or 19 or 13&5ci4 |
| Colorado Springs | El Paso7 | 5B | 15ci or 19 or 13&5ci4 |
| Fort Collins | Larimer7 | 5B | 15ci or 19 or 13&5ci4 |
In plain terms, "5ci or 13" means R-5 continuous insulation on the wall surface or R-13 in a stud cavity. "15ci or 19 or 13&5ci" means R-15 continuous, R-19 in the cavity, or R-13 in the cavity plus R-5 continuous.4 Where basement walls are insulated, the code runs the insulation from the top of the wall down to 10 feet below grade or to the floor, whichever is less.4 There's an exception for unconditioned basements that meet a list of conditions, and footnote f exempts Warm Humid locations.4 Local adoption and amendments vary, so your contractor pulls the permit and books the inspections under your local code.
When you insulate basement walls, what goes against the concrete matters as much as the paint did. The DOE says fiberglass batt or cellulose insulation should not touch foundation walls.2 Rigid foam panels must adhere completely to the wall with no air gaps behind them.2 Building Science Corporation recommends rigid or spray foam here because it allows drying, resists moisture damage and doesn't support mold growth.3
If you're weighing a coat of paint against a full build-out, you can get a written quote for finishing your basement and compare. Local pages cover basement finishing in Atlanta, finishing a basement in Denver, basement finishing in Colorado Springs and finishing a basement in Fort Collins. If your basement was finished years ago and the walls behind the drywall got wet, that's a basement remodeling job, not a paint job.
What should you ask your contractor before painting or finishing?
Ask where the moisture is coming from before you talk about color. A good contractor checks the walls for moisture at the estimate and writes the prep into the quote. Then ask what product goes on the wall, whether it lets the wall dry, and what happens if water shows up later.
- Is this damp from condensation, from outside water, or both?
- What prep is included: scraping, cleaning, patching and drying time?
- What paint or coating are you using, and is it oil, alkyd or epoxy based? Those don't belong on the interior of basement walls.2
- If you're selling a sealer or waterproofing coating, what does its label claim, and what outside drainage work does the house need?
- If I'm finishing the space, what insulation meets code for my climate zone, and will you pull the permit?
Basement Remodeling Co. matches you with one vetted, licensed basement contractor for your metro. That contractor books a free on-site estimate, checks moisture and ceiling height, and gives you a written, itemized quote. Nothing starts until you sign. You can find the basement contractor for your ZIP code or read about a larger basement renovation if the walls are only one part of the job.