For years crown molding has been almost exclusively made from wood. Because of the high price of wood crown molding foam molding has become popular. It is more cost effective than wood and is easier to work with than wood.

Foam crown molding is lightweight and flexible and it is usually installed with an adhesive rather than nail. It is easy to cut by hand with a sharp carving knife. Because it is flexible you can create perfect joints and seams while hiding any imperfections.

There are two methods for painting foam molding, spray painting or brush painting. Spray painting requires less work, fewer materials, and is faster. Brush painting is slightly more labor intensive than spray painting.

Spray painting foam crown molding:

Spray paint before installing by applying several thin even coats taking care not to oversaturate the foam with paint. Painting all the pieces an let dry before installing.

Brush painting crown molding:

Unlike spray painting, brush painting requires the foam to be coated with thinned drywall joint compound as a sealant before painting. This helps create a smooth surface to paint. Install the molding before sealing and painting. Mounting first gives you the benefit of foam's compressibility to create clean corners and seams before you harden the material with sealant and paint.

After the molding has been installed, protect the room from paint and joint compound with drop cloths and painter's tape as needed. Prepare the drywall molding sealer compound mix. The dry wall sealer should be thinned until it's the consistency of paint.

Brush a thin coat of sealer onto the entire surface of the molding. The joint compound will dry quickly so you'll be able to start applying a second coat as soon as you finish the first go-around. Only two coats are required for a smooth surface. Once the sealer is applied, allow the molding a full 24 hours to completely dry.

Sanding the dried joint compound should not be necessary unless you spot a flaw. If you need to sand the compound down, use a fine grit sandpaper. When you're satisfied with the coating surface, proceed to paint the molding with white paint.

Avoid using any oil-based paints on the foam. Use a latex paint. When you are finished applying the sealer and paint, the molding will be bright white.

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