What to Clean Walls With Before Painting | Full Guide

Use mild soap and water for most walls, vinegar or degreaser for kitchens, and a bleach solution for bathrooms. Always rinse and let dry. Clean walls properly, and your paint will bond better, last longer, and look smoother.

Wall Cleaning Cheat Sheet: 

• Mild dish soap is perfect for bedrooms, hallways, and low-traffic areas

• Kitchens need degreasers or vinegar to cut through cooking residue

• Bathrooms require a diluted bleach solution to kill mold and mildew

• For smoke stains, use TSP or vinegar to avoid bleed-through

• Glossy or previously painted walls must be lightly sanded and wiped

• Skipping the rinse step is a top cause of adhesion failure

At ProSmart Painting, we’ve rescued more paint jobs than we can count, many ruined not by bad paint, but by poor prep. Our crews take the time to clean, degloss, and dry every surface the right way, so your finish actually lasts.

Keep reading to learn exactly what to clean your walls with before painting, based on room, surface type, and real-world conditions.

What to Use to Clean Walls (Based on Room Type & Condition)

General Living Spaces

In bedrooms, hallways, and other low-traffic areas, a solution of mild dish soap and warm water is often all you need. Use a soft sponge or microfiber cloth to gently clean the surface without damaging the drywall. Avoid abrasive scrubbers, which can leave marks that show through paint. After cleaning, rinse the area with a clean damp cloth to remove soap residue, and allow the walls to dry fully before continuing.

Kitchens

Kitchens require extra attention due to grease buildup around cooking areas. Use a degreasing detergent or a vinegar-based solution to break down oil and residue. A Reddit user shared success using a mix of vinegar and baking soda near the stove, a natural alternative that cuts through grime without harsh chemicals. Always rinse well afterward to ensure no residue remains that could interfere with adhesion.

Bathrooms & Laundry Rooms

These spaces are prone to mildew due to high humidity. Use a bleach solution (typically 1 part bleach to 3 or 4 parts water) to kill mildew on walls. Wipe down the area thoroughly and then rinse well with clean water to prevent bleach from affecting paint color. A common concern raised on Reddit is whether bleach is safe for drywall. The answer: only if used in moderation, rinsed thoroughly, and applied with proper ventilation.

Smoky or Stained Walls

For walls exposed to smoke or nicotine, trisodium phosphate (TSP) is a go-to solution for deep cleaning. It cuts through residue that can bleed through paint. In sensitive areas like nurseries, vinegar and water may be used instead as a gentler, safer alternative, though it may require more elbow grease and repetition.

Glossy or Previously Painted Walls

Glossy finishes can repel paint, so it’s important to de-gloss the surface by lightly sanding. Focus on scuffing the surface enough to dull the sheen, not remove the paint entirely. Reddit users recommend sanding sponges over paper for more control around trim and corners. After sanding, wipe down the dust with a damp cloth before priming.

High-touch Areas (doors, hallways)

Door frames, light switch areas, and baseboards collect oils from skin and repeated contact. Alcohol-based cleaners like isopropyl alcohol work well to remove oils and residue. These surfaces should be cleaned and dried thoroughly before applying primer, especially if you're working with high-durability paint finishes.

Step-by-Step: How to Clean Your Walls for Painting

Cleaning your walls before painting is a simple but essential process. Done properly, it sets the stage for a smooth application, long-lasting finish, and fewer paint failures. Here's how to do it right:

1. Remove furniture or cover with drop cloths. Move furniture out of the way or cover it with canvas or plastic drop cloths to protect it from splashes, drips, and cleaning residue.

2. Dust walls with dry microfiber cloth or vacuum. Start by removing loose dust and cobwebs. A microfiber cloth or vacuum with a brush attachment works well. This preps the surface and prevents dirt from smearing when wet.

3. Mix appropriate cleaning solution by wall condition. Choose your cleaning method based on room type and surface issues. Mild soap and water for general areas, vinegar for grease, bleach for mildew, or TSP for smoke-stained walls.

4. Use soft sponge or cloth to gently scrub. Work in small sections, from top to bottom. Apply light pressure using a soft sponge or lint-free cloth. Avoid over-saturating the wall, especially if it's unsealed drywall.

5. Rinse thoroughly to avoid soap or bleach residue. After cleaning, go over the wall with a clean damp cloth to remove any remaining detergent, vinegar, or bleach. Residue left behind can interfere with paint adhesion and color.

6. Let walls dry completely before sanding, patching, or priming. Moisture trapped under primer or paint causes blistering and poor curing. Wait until the walls feel bone dry to the touch, this may take a few hours or overnight, depending on humidity.

If you’d rather have a pro handle it from prep to finish, book a consultation with a local painter who can get it right the first time.

What NOT to Do When Cleaning Walls Before Painting

While cleaning is critical to painting success, doing it wrong can create a whole new set of problems. These common mistakes can compromise adhesion, damage surfaces, or leave you with a frustrating finish.

Don’t overuse bleach

Bleach is effective at killing mold and mildew, but using it too heavily or failing to dilute it properly can damage drywall and cause discoloration under paint. Always follow recommended ratios and rinse thoroughly.

Don’t leave soap residue

It’s not enough to wipe the walls, you have to rinse them too. Soap left behind forms a thin film that repels primer and paint, resulting in uneven coverage, peeling, or bubbling.

Don’t skip the rinse step, even with natural cleaners

Cleaners like vinegar may seem harmless, but they still leave behind acids and residues that interfere with paint adhesion. Every cleaner, whether natural or chemical, needs to be rinsed with plain water.

Avoid overly abrasive pads or tools

Steel wool, rough scrubbing pads, and harsh sponges can gouge drywall, leaving behind texture variations that become more visible once the paint is applied. Stick with soft sponges or microfiber cloths unless you’re sanding intentionally.

By avoiding these prep pitfalls, you’ll give your paint the best chance to bond properly and look great long after it dries.

Special Scenarios & Prep Mistakes to Avoid

Every wall is different, and some require extra attention before paint can even touch the surface. Here’s how to handle common special cases and avoid mistakes that could ruin your finish.

Painting Over Wallpaper

It’s generally not recommended to paint over wallpaper. The seams often telegraph through the paint, and any leftover glue can react with moisture and cause bubbling or peeling. If you do remove wallpaper, make sure all adhesive residue is thoroughly cleaned off. Even invisible glue can ruin the look and longevity of your paint job.

Spackle & Patching Dust

After patching holes or smoothing dents with spackle or joint compound, always wipe those areas with a damp cloth before applying primer. A Reddit user pointed out that skipping this step led to dull, patchy results in the final coat. Dust acts as a barrier, preventing even primer from sticking properly, so always clean before moving on.

Mold & Water Damage

Before painting over walls previously exposed to moisture, clean the surface thoroughly and use a mold-killing primer to prevent regrowth. If the drywall feels soft or shows signs of crumbling, don’t just paint over it, that area may need to be replaced or sealed with a drywall repair product first. Painting over moisture-damaged walls without repair will only lead to failure later.

Prep Right or Repaint Later

Clean walls are the foundation of any great paint job. When you skip proper prep, even the best paint can fail to stick, cure unevenly, or peel within months. A quick clean with the right solution can mean the difference between a finish that lasts and one that disappoints. Don't rush it, dry, dust-free walls are non-negotiable.

Need help getting it done right? Contact ProSmart Painting today for expert prep and flawless results.