How to Paint Trim Like a Pro

Five-Step Process for Painting Trim

The key to a professional trim paint job is careful preparation. If you’re painting both walls and trim, paint the trim first! Let the trim paint overlap onto the wall by about a half inch; it’s much easier to cut wall paint up to the edge of the trim. You’ll also save a lot of time by not taping around the entire room.

Step 1: Clean the trim

Trim collects lots of dust and dirt; don’t skip this step! Wash all trim surfaces thoroughly to remove dirt, dust, or debris using a sponge and a mixture of water and mild soap. Be sure to clean the ledges above doors and windows too. Rinse with clean water and let it dry completely.

Step 2: Prep the trim

Check your trim for rough spots, scratches, or bumps and use 120 grit sandpaper to smooth any damaged areas. Use a putty knife to fill nail holes and cracks with a wood filler. Allow the filler to dry completely, then use 320 grit sandpaper until you have a smooth, even surface. 

Also be sure to inspect it for any gaps between the wall and trim—now is the time for fresh caulk before new coats of paint go on. Apply a bead of paintable caulk along the corner where the trim meets the wall. Smooth the caulk with a damp rag or a caulking tool and let it dry completely. 

Don’t forget to clean again when you’re done! Use a tack cloth or a damp rag to wipe off the dust from sanding and any caulk residue. 

Step 3: Prime the trim (if needed)

In many cases, you can skip right to painting. However, if your trim is damaged or stained, or if you are making a significant color change, we recommend priming first. If you are painting your trim a dark color, ask a Ring's End sales team to have it tinted for the most even color. Using a 2.5″ angled soft bristle paint brush, apply a thin coat of primer to every trim surface, starting at the top of the room—molding, windows, doors—and working your way down. Long, smooth strokes in the direction of the grain will help to avoid brush marks. The primer may not completely hide what’s underneath – this is fine! Let the primer dry completely before moving on to the next step.

Step 4: Apply the first coat of paint in 2-3 foot sections

Start with a clean paint brush; dip it into the paint about an inch, and then tap it firmly on the edge of the can (don’t wipe off excess paint). This ensures the bristles stay loaded with paint; don’t overload the brush because this will cause drips.

Working in 2-3 foot sections, apply the paint the same way you applied the primer, with long, even strokes in the direction of the grain. When you finish a section, start another section two feet away and work back towards your first section, then feather the edges together. Where the trim meets the walls, overlap the trim paint onto the wall (or the masking tape) about a half inch; this makes it easier to create a crisp edge.

Pro Painter’s Tip: Never pass the brush across wet paint, because it will leave a mark. Always start two feet away and feather the painted sections together for a professional finish without brush marks.

Step 5: Apply a second coat of paint and let it cure

Make sure the first coat of paint is dry before applying a second coat. Check the instructions on your paint can for the “drying time to recoat”. This may take several hours depending on the temperature and humidity. Once the second coat is finished, allow plenty of time for the paint to dry. Be gentle with the trim and avoid scrubbing it until the paint has fully cured – this can take up to two weeks.

Painting interior trim with professional techniques takes time, but it’s well worth the effort to achieve a smooth, lasting finish. Choose high-quality paint, spend some time practicing your technique, and you’ll be amazed at the results.