Thermal & Ignition Barrier Coating for Spray Foam Insulation

Code-approved DC315 coating for alternative spray foam thermal and ignition barrier

Basement walls covered with spray foam and a fire retardant coating

Advanced Basement Systems uses an intumescent coating as a thermal and ignition barrier over spray foam on unfinished basement walls.

Some foam insulation applications require a thermal barrier to prevent or delay fire spread when exposed to potential fire hazards. Foam insulation can be left exposed in some areas of a home or building, while others must be covered with a thermal barrier to ensure fire safety and building code compliance. The Ontario Building Code requires a 15-minute thermal barrier between foam insulation and the interior spaces of the building. Advanced Basement Systems uses Firelock DC315, an intumescent coating that’s applied over spray polyurethane foam (SPF) to achieve a “15-minute alternative to thermal barrier” and “5-minute ignition barrier.” The thermal ignition barrier coating can be used as a code-compliant alternative to drywall in basements, garages, or other areas within the home where drywall isn’t practical.

Why does spray foam insulation need to be covered?

Foam insulation material will ignite if it’s exposed to an open flame. While many foam insulation products are “Class 1” fire-rated according to ASTM-E84 and contain fire retardants, the building code still requires a thermal barrier to slow the spread of a potential fire.

There are a few acceptable options for thermal barriers: 

  • Gypsum board
  • Plywood
  • Drywall
  • Intumescent paint or spray-on coating, such as DC315

What is an intumescent coating and where is it used?

An intumescent coating is usually the most cost-effective thermal barrier option in storage or service utility areas where drywall or other thermal barrier options aren't practical. When exposed to heat or flames, the special coating expands and forms a char that acts as an insulating barrier, slowing the spread of fire and protecting the insulation material from intense heat.

There are many areas of a home or building where an intumescent coating can be used as a thermal barrier:

  • Basement or garage walls that remain exposed (without drywall)
  • Attics and crawl spaces used for storage
  • Ceilings in basements or garages that remain exposed
  • Any areas where drywall or other wall coverings aren’t practical

Get started with a free home insulation estimate

If you need insulation in the basement, garage, attic, crawl space, or another area in the home that won’t be covered with drywall, you can trust Advanced Basement Systems for proper spray foam installation that meets building code and fire safety standards.

We are a trusted insulation company in Ontario, proudly offering free insulation estimates in London, Windsor, Sarnia, and surrounding areas. If you have questions or want to schedule a free estimate for spray foam insulation, call 1-844-320-1542 or fill in our online contact form!

Looking for a price? Get a no cost, no obligation free estimate.

our service area

We serve the following areas

Our Locations:

Advanced Basement Systems
23576 Prince Albert Road
Chatham, ON N7M 5J7
1-226-706-2439


Advanced Basement Systems
199 Exeter Rd Unit E
London, ON N6L 1A4
1-226-271-8708
Service Map
Service Area
Free Quote