Things You'll Need
Trisodium phosphate or TSP substitute
Shellac primer or water-based bonding primer
Synthetic fiber paintbrush
White acrylic latex paint
TSP is unavailable in some communities for environmental reasons, but there are eco-safe alternatives labeled as TSP substitutes. Both types of products must be mixed with water before use.
A poor paintbrush can shed fibers in the paint and leave visible lap marks. Use a better grade of synthetic-fiber paintbrush for best results, especially when using higher-gloss paints.
You can clean water-based paint from a paintbrush using ordinary soap and water. To clean shellac from a paintbrush, soak the fibers in a container of denatured alcohol.
Higher-gloss acrylic latex paints are more impact- and abrasion-resistant than flatter paints, offer superior coverage of errors, and make a white paint appear brighter.
If your wood trim had been painted before 1978, it must be tested for the presence of lead paint before any stripping or scraping can take place. Ingesting or inhaling lead paint dust can lead to health consequences, especially for children in the home.
White trim serves as a visual baseline to the rest of the room's color scheme, adding snap to even lightly-pigmented walls and furnishings. Whether you're painting unfinished new wood or repainting antique wood trim, the key to an attractive paint job is proper surface preparation.
Ventilate the room. Clean previously painted or varnished wood trim. Sponge it down with trisodium phosphate or a TSP substitute. Wipe off the wood trim with a slightly wet sponge to remove any TSP residue. Allow the trim to dry.
Smooth the trim using a small square of 180-grit sandpaper on any rough or noticeably uneven portions of previously painted or stained wood. Do not sand to the extent of stripping off the old finish. Use the sandpaper to rub out any splinters or significant surface irregularities on unpainted wood.
Remove the sanding dust with a tack cloth.
Spread wood putty into any deep cracks or indentations in the wood, using a putty knife. Allow the putty to dry completely, then sand it down to a smooth finish level with the adjoining wood segments. Clean off the sanding dust with a tack cloth.
Affix painter's tape to any wall, floor or ceiling surface that adjoins the wood trim.
Apply white pigmented shellac primer to the wood trim, using a synthetic fiber paintbrush. If the trim previously was painted with a high-gloss enamel paint or stained and varnished with a high-gloss polyurethane, apply a water-based bonding primer instead. Allow the primer to dry thoroughly for two to three hours or as indicated on the label.
Brush on a coat of acrylic latex paint in the desired sheen -- semi-gloss or gloss are standard for trimwork -- using a high-quality synthetic filament brush. Allow the paint to dry thoroughly for two to three hours or as indicated on the directions.
Apply a second coat of the acrylic latex paint. Wait one to two days before removing the painter's tape.
- Sherwin-Williams: Tips for Using Trim to Highlight Color
- Paint Quality Institute: Prep, Prime and Paint -- Wood
- Popular Woodworking: Rules for Sanding Wood
- Woodworkers Journal: Best Wood Filler
- PaintPRO: Priming Interior Woodwork, Trim and Crown Molding
- Popular Mechanics: Bristle Basics -- Which Paintbrush Should You Use?
- Paint Quality Institute: Paint Advice
- Jaworski Coatings Inc.: Painting Wood Trim
- Today's Homeowner: Homeowner’s Guide to Paint Primer
Mike Matthews is editor of Green Building Product News, a national publication that covers sustainable innovations in building and remodeling, and he has spoken at national conferences on green building. He has also served as founding editor of "Paint Dealer" magazine.