Can You Brush Urethane Over Latex Paint?

Primed Foundation

• Although you're most interested in the high-gloss finish, the foundation beneath the latex paint is very important. If your latex paint is applied to two coats of a quality primer, such as Kilz, the overall finish will be much better. Because of its glossiness, urethane tends to magnify imperfections in the surface beneath. A smooth latex surface, boosted by a couple of coats of primer, will look much better than a choppy latex surface that lacks foundation.

Double Latex

• Again, before you get to the urethane, make sure your latex paint surface looks good. For most colors of latex paint, you should apply two coats. For very dark shades, you may need to put on additional coats until you get a solid, opaque finish.

Sand Latex

• Using the finest sandpaper you can find or a pad of steel wool, sand the dried latex paint. Don't be aggressive with your sanding. Your purpose in sanding the latex paint is to smooth out any rough spots or air bubbles to prepare the paint for its urethane coat. After you've gently sanded all over, use a hair dryer to blow the dust off the surface. If you're concerned about the mess made by the hair dryer, just wipe the surface down with a clean cotton cloth.

Applying Urethane

• To apply the urethane, use a high-quality paint brush, and apply the urethane with long, even strokes. Work quickly so you never have any dry edges, which will show up as lumps when the entire surface is dry. One coat should be enough, but if you want the surface to be extra durable, sand the urethane after it has dried, wipe it clean and apply one more coat.