Can a Spray Foam Barrier be Applied to Any Surface?

Spray foam is a great tool for insulating, weatherizing, and protecting from fire. It can be applied to horizontal and vertical surfaces. Once it is cured, it can be an air barrier and add thermal control layers . A foam barrier provides some of the highest R-values per inch available. The higher the R-value, the better it insulates per inch of thickness.

Sounds great, right? Does that mean you can put it anywhere and everywhere? Not quite.

Can Spray Foam be Applied to Any Surface?

For one, you need to ensure the environment is right. Cold weather can cause problems with foam applications, leading to the two most common problems: shrinkage and poor adhesion to the substrate.

As you further read the product descriptions, you will see that the manufacturers say the products should not be applied when the relative humidity exceeds 80% or the surface to be coated is less than 40°F or less than 15°F above the current or forecasted dew point.

You don't want your area to be too hot or too cold, which may be a problem in attics and crawl spaces. A foam barrier is best applied when ambient temperatures are between 50°F and 95°F. While the product can be applied at lower temperatures, viscosity may be a problem. If applied at too-high temperatures, there may be a risk of runs or sags.

It is important to point out that we’re talking about the substrate surface temperature, not the ambient air temperature.

Our Top Recommendations for a Foam Barrier Paint

When shopping for a foam barrier, you have five top options. They include:

Contego HIGH SOLIDS Fire Retardant Paint/Primer for Steel

Specially designed for structural steel, this new formula means you can get the same great results using 20% less product! A thinner coat means less time and less labor costs to get the desired rating. It is designed to protect a wide range of building materials, including structural steel, spray polyurethane foam insulation, and many more.

DC315 Thermal Barrier Paint for Spray Foam

This is an intumescent coating applied over Spray Polyurethane Foam (SPF) to achieve a “15 Minute Alternative to Thermal Barrier” and “5 Minute Ignition Barrier.” It has one of the best coverage rates for foam at 115 sq ft/gallon, making it very cost efficient.

FireGard Fire Retardant Waterproof Paint

This is a waterproof, fire-retardant paint that is an extremely durable coating that is especially useful for treating exterior wood. It also serves both as a 5-minute ignition barrier and a 15-minute thermal barrier over Spray Foam Insulation (SPF). It is one of the only coatings that can go over exterior SPF. It's available in 24 colors!

F10E Intumescent Paint for Spray Foam Insulation

This product is perfect for walls, foam, attics, and crawl spaces. It expands up to 2,000% in order to be an interior coating that provides oxygen starvation to fire.

Contego Fire Retardant Paint & Primer - Multi-Purpose Intumescent

This product provides exceptional protection from heat and fire. Because it is designed to protect a wide range of building materials, you're sure to find many places within your home or commercial building that would benefit from its coverage.

If you have any questions as to which product is the right foam barrier for you, reach out and ask us.