Mulch Causes Fire Outside Vienna Home: Fire Department

VIENNA, VA — Fairfax County Fire and Rescue have determined that spontaneous combustion of mulch caused a Vienna house fire Monday.

Around 4:30 p.m., units responded to a single-family home in the 1900 block of Baton Drive. Smoke was showing from the exterior of the home, and fire was limited to the exterior with minor extension into a detached garage.

No injuries were reported, as no residents were home at the time. A passerby had observed the fire and called 911. Smoke alarms did not activate due to the fire's location.

Fire investigators tracked the source to a mulch bed with recently added mulch. Damages were estimated to be around $25,000. No residents were displaced.

The fire department cautions residents that mulch is flammable and produces high temperatures when decomposing.

"Spontaneous combustion can happen when a decomposing material generates enough heat to ignite without an outside source," reads a fire department statement. "Because of this, a large enough pile of mulch or chips can create sufficient heat to spontaneously combust. Mulch fires are more likely to start when the weather is hot and it has been dry for an extended time."

Fairfax County Fire and Rescue recommends the following tips for safe mulch use:

• Avoid placing mulch against a building. Provide a minimum of an 18-inch clearance between mulch beds and combustible building materials, such as wood, vinyl siding, and decks. Consider using non-flammable landscaping materials like rocks or pebbles close to your home or building.
• Provide proper receptacles for smoking materials at entrances to buildings or outside your home and empty regularly. Do not mulch these areas.
• Do not compact the mulch.
• Keep mulch beds moist when possible.
• Watch for mulch fires, especially when mulch is fresh or the weather is very hot, dry, or windy.
• Large piles of mulch can spontaneously combust from all the heat they generate. The distance between mulch piles keeps a fire from spreading from one pile to another or to a building.