How to Sand Baseboards Before Painting: Easy Prep Tips for Perfect Results

Painting your baseboards (also known as floor moldings or skirting boards in some regions) is an easy way to refresh your home without major renovations. It can also help protect them from average wear and tear. Sanding your baseboards before painting makes the final result look cleaner and more intentional.

Professional painters use this trick to make primer and paint adhere properly for a clean finish that won't chip or peel. Learn how to sand baseboards before painting, including the tools you’ll need to finish the job and tricks to make the final result look great.

Repainting your baseboards is a small change to your overall interior, but it’s also time-consuming enough that you don't want to have to redo it. Prepping your baseboards by sanding them first will help you achieve a smooth, uniform finish.

Sanding creates an even surface by removing any remaining paint or glaze you’ve stripped from the board. Paint also sticks better to slightly roughened surfaces. If you’re painting over existing paint, it could start chipping faster if you don’t sand your baseboards.

For best results, repair any damage to the baseboard before you start sanding. Fix seams, corners, and caulk lines, then sand to level minor dings and filler. You’ll get a flush, professional surface you can paint with fewer coats. Your cut lines will also be cleaner. Use a heavy-duty floor scraper for trickier scraping jobs.

When you know how to sand baseboards quickly, you can finish each job faster and achieve a clean result. Your level of prep could differ if you’re working in an old house or if you have to strip multiple layers of old paint from the baseboards.

First, lay down drop cloths to protect your flooring. Then, after you've decided whether to paint the walls or the trim first, follow these steps to get the best finish before you paint your baseboards.

Step 1: Clean the Surface Before Sanding

Lived-in baseboards usually need a thorough cleaning before painting to remove any dirt and grime that's built up over the years. Even newer baseboards will need a light cleaning to remove any debris or old caulk.

Cleaning before you sand also makes it easier to sand baseboard trim. Sandpaper can get stuck on dirt and grime. Your baseboards might also be uneven if you skip this step before sanding.

Start by vacuuming with a brush to clear up the dust. Next, prep a mild cleaning solution, such as warm water with a little dish soap, vinegar, or cleaner. Use a microfiber cloth or a drywall sanding sponge to wipe down the baseboards and remove dirt and grime.

If your baseboards are really dirty, try a steam cleaner or make a paste with baking soda and water. Let it sit on tough stains before cleaning them. Look for any loose caulking and remove it.

Step 2: Repair Caulk Lines, Dents, Gaps, and Corners

As you prep your baseboards, look for deep cracks, old caulk lines, and holes, dents, or gaps. Making repairs before you sand keeps you from having to re-sand later. It also keeps paint coats more even.

Remove old caulk at the seams between the wall and the baseboard. Your old caulking might still work, but it often yellows with age. Removing and replacing it makes your baseboards look new. It also helps seal any cracks that formed in the old caulking.

Patch any cracks, holes, or damaged corners with wood filler. Overfill it slightly, because the filler will shrink.

Let the filler cure fully before you start sanding. Check the packaging before getting started. Some wood fillers cure in 15 minutes, while others need up to 24 hours.

Add the Caulk Aid from Hyde Tools to your kit to quickly strip old caulking. The high-impact blades strip caulking from any surface and have a sharp point for corners.

Step 3: Choose the Right Grit

The right sandpaper grit is essential for prepping your baseboards. If the grit is too fine, it won’t remove enough surface material to allow your paint to adhere. Too coarse, it can damage your baseboards.

If your baseboards have layers of varnish and old paint, start with at least 80-grit sandpaper. For newer baseboards or baseboards with minimal damage, medium 120-grit sandpaper is enough to remove any remaining paint or varnish evenly.

You can follow up with fine-grit sandpaper of 180 to 220 to smooth any remaining rough edges. For a truly professional finish, sand your baseboards with fine-grit sandpaper between paint coats.

Step 4: Sanding Techniques That Deliver Smooth Results

Proven sanding techniques will make your baseboards smooth without the extra elbow grease. Start with a medium grit to remove varnish and paint and even out large imperfections. Focus on the holes and cracks you've filled. Make sure they’re even with the rest of the baseboard.

Finish with a fine-grit sanding block or fold a piece of sandpaper to smooth rough spots and detail curves and edges. For best results:

• Sand with the wood grain: Follow the wood’s natural grain to avoid scratching your baseboards.
• Apply consistent pressure: Whether you’re using an electric sander or sanding by hand, maintain steady pressure on the whole board.
• Use the right tools: Choose sanding tools for each part of the baseboard. Electric sanders are great for flat surfaces, but sandpaper blocks give you more control on curved pieces.

Step 5: Clean Up Dust for a Perfect Paint Base

Sanding is a dusty process. Leftover dust can stick to the paint, making your finish look uneven.

Save time with dust-free sanding systems. If you don’t have one handy, vacuum and clean with a microfiber cloth after you finish sanding. Check out these dust-free sanding tips to shave time off this step.

Once you’ve removed any dust and debris, apply your primer coat and let it dry. Then apply paintable acrylic-latex caulk to close the gaps between the wall and the baseboards before your final coat of paint. Use the padded end of your caulk aid to smooth the new bead. You're now ready to paint your baseboards.

Hyde Tools offers a range of pro-grade painting tools for your baseboard projects. Our Professional Dust-Free Pole Sander includes a pole that lets you reach every spot on your baseboard, and its vacuum attachment sucks in dust as you sand.

Sand and paint your baseboards in the garage or your workshop by pulling them off the wall first. Our molding puller is designed to remove moldings, baseboards, and trim without damaging them.

Get your baseboards ready for a fresh coat of paint. Hyde Tools has dust-free sanders, sanding blocks, and other jobsite-ready supplies you need. Add them to your kit to quickly refresh your home with like-new baseboards.