Getting professional results when painting interior doors and trim starts with using the right paint and the proper tools. A few tips and best practices can also make the difference between a so-so job and a top-notch one, and who doesn't prefer the latter?
Tip 1: Use Trim Enamel
You can still find oil-based trim paint in quart cans, but you seldom need it -- latex is easier to handle, dries faster and cleans up with water. Don't be tempted to use up an old can of wall paint -- trim enamel is designed to be thicker so it stays on your brush, and it covers better. You have three choices when using trim enamel -- gloss, semigloss and satin. Flat paint picks up fingerprints and other smudges and isn't an appropriate choice for trim or doors.
Tip 2: Take the Door Down
You can paint a door while it's hanging, but the results are usually inferior to those you can get while painting it flat on a pair of sawhorses. The bottom edge of the door and the areas around the hinges are especially prone to brush marks if you paint the door while it's hanging, and visible brush marks are a sign of an amateur. Remember to take all the hardware off the door before painting it.
Tip 3: Use a Paintbrush
Rollers are for walls -- roller marks on wood trim speak of a painter who was in a hurry. Using a roller speeds up the job of painting door panels, but you should brush over the roller marks while the paint is fresh. Be sure to use a synthetic-bristle paintbrush for latex enamel; the water in latex paint softens natural bristles and makes them flaccid.
Tip 4: Brush With the Grain and Toward the Wet Edge
The trick to making your brush strokes disappear is to blend them with the wood grain, and you can do that only if they run in the same direction. When brushing doors, that usually means brushing horizontally along the top, middle and bottom trim that encloses the panels. Finishing each stroke on the fresh paint you applied on the last stroke -- which is called brushing toward the wet edge -- also helps brush strokes disappear.
Tip 5: Use Masking Tape Wisely
Instead of masking tape, professional painters often rely on a keen eye and steady hand to paint straight lines between trim and walls, even if the colors are significantly different. This saves time, but more important, it eliminates the need to pull tape off of another surface that may be freshly painted and ruin the paint job. In addition, masking tape can be unreliable -- paint often seeps underneath and leaves blotches that can be difficult to fix. If you have to use masking tape, control seepage at the interface between a wall and a piece of trim by painting over the tape with the wall color and letting the paint dry before painting the trim.
Tip 6: Avoid Dividing Lines on Door Jambs
When you paint one side of a door a different color than the other, it's sometimes a good idea to paint the jambs to match. Instead of forming a dividing line down the middle of the jamb, which is difficult to accomplish cleanly, try a different strategy. Paint the entire inside of the jamb the same color as the jamb on the back side of the door, which is the side opposite from which it swings; the jamb is most visible from that side of the door.