How to Coat Styrofoam

Coating Styrofoam makes it more durable.

Coating Styrofoam may be a necessity for several reasons. Styrofoam on its own breaks easily and is difficult to paint. Adding a coating over the Styrofoam gives it a more durable exterior and also makes it accept painting and coloring. Coated Styrofoam is likely to last longer than non-coated Styrofoam. Use three main ways to coat Styrofoam for different finish effects.

Things You'll Need

• Plastic roofing sealer
• Foam coating
• Trowel
• Water-based adhesive
• Paintbrushes
• Rubber gloves
• Eye protection
• Old clothes

Instructions

Foam Coat

1. Cover the Styrofoam in a hard coating that is very durable using the foam coat. Wear eye protection and rubber gloves when working with any coating for Styrofoam to protect your eyes and hands from the coatings. Wear old clothes in case the coating spills onto your clothing.

2. Spread a thin layer of foam coating on the surface of the Styrofoam with a paintbrush. Allow the coat to dry for four hours. Do not allow anyone to touch the Styrofoam during the drying period.

3. Apply a second layer of foam coating as thickly as possible. Reach a thickness of about 1/8th inch or thicker. Allow the coat to dry for hour hours.

4. Apply one last coat of foam coating to add smoothness to the Styrofoam. Spread the coating over the Styrofoam with a trowel. Allow the coating to dry overnight.

Roofing Sealer

1. Paint roofing sealer over the Styrofoam for a more flexible coating that receives paint well.

2. Paint a thin coat of sealer onto the Styrofoam with a paintbrush to seal in any crumbles. Allow the paint to dry for two hours.

3. Apply two more coats of roofing sealer on top of the seal coat. Allow each coat to dry for one hour between coats. Wait 24 hours before touching or painting the surface of the Styrofoam.

Adhesive Coat

1. Produce a rubbery effect on the surface of the Styrofoam using a water-based adhesive coating. This coating is highly flexible and has a large amount of give.

2. Apply the adhesive with a paintbrush. Allow the adhesive to dry for two hours.

3. Apply one additional coat over the surface of the Styrofoam. Use a trowel to smooth out the adhesive over the surface of the Styrofoam. As with the other coatings, wait overnight or 24 hours before touching or working with the Styrofoam again.

References

• Fix Supply: Steve's Coating for Styrofoam
• Upstage Review: Styrofoam Coatings