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Spraying a treatment across ground cover
Photo Anastasiya Badun / Unsplash

Fire Retardant Gel & Spray

Coat siding, decks and fences with a protective barrier before you evacuate.

Fire-blocking gels and long-term retardant sprays create a heat-absorbing barrier on wood, vinyl and composite surfaces. Gels (Barricade, Thermo-Gel, FireIce) are applied with a hose-end sprayer minutes before evacuation and last several hours. Long-term retardants (Phos-Chek Home Defense) are applied days or weeks ahead and stay effective until washed off by rain.

Before you buy

  1. Gels are a last-minute product: apply when evacuation is ordered, not the week before. They dry out in 6–24 hours depending on heat and wind.
  2. Long-term retardants are seasonal: apply to fences, decks and mulch beds in early fire season and refresh after heavy rain.
  3. A 5-gallon (19 L) gel concentrate typically covers a 2,000 sq ft (185 m²) home exterior. Buy two if you have outbuildings.
  4. Check the applicator: hose-end sprayers need ~40 psi. If your pressure drops in an emergency, a backpack sprayer is more reliable.
  5. Gel is not a substitute for sprinklers — it protects surfaces from radiant heat and embers, but it does not stop a crown fire.