Termite Treatment Guide: Signs, Prevention & Costs

Types of Termites

Subterranean Termites

The most destructive and common type in the US. Live in underground colonies (100,000 to 1 million+ individuals). Build mud tubes (pencil-width tunnels on foundation walls) to travel between soil and wood. Require contact with soil moisture. Found in every state except Alaska. Cause 95% of all termite damage in the US. Formosan subterranean termites (a more aggressive species) are established in the Southeast and expanding.

Drywood Termites

Live entirely inside the wood they consume (no soil contact needed). Smaller colonies (up to 2,500). Common in coastal and southern states (California, Florida, Gulf Coast). Signs: small piles of frass (tiny fecal pellets that look like sawdust or coffee grounds) below infested wood. Harder to detect than subterranean termites.

Dampwood Termites

Infest wood with high moisture content. Larger than subterranean termites. Common in the Pacific Northwest and other humid regions. Rarely infest homes that are properly maintained (they need very wet wood). Fix moisture problems and they go away.

Signs of Termite Infestation

Mud tubes: Pencil-width tubes of mud on foundation walls, piers, or sill plates. The most definitive sign of subterranean termites. Break open a tube — if you see live termites, the infestation is active.

Damaged wood: Wood sounds hollow when tapped. Surface may appear undamaged but the interior is consumed. Subterranean termites eat along the grain, leaving a layered (honeycomb) pattern.

Swarmers: Winged termites emerging in large numbers (usually spring). Often confused with flying ants (termites have straight antennae, equal-length wings, and a broad waist; ants have elbowed antennae, unequal wings, and a pinched waist). Discarded wings near windows and doors.

Frass: Tiny pellets (drywood termites push fecal pellets out of small kick-out holes). Looks like sawdust or pepper. Found below infested wood.

Treatment Options

Liquid barrier treatment ($500-$2,500): Chemical termiticide applied in a trench around the foundation perimeter. Creates a continuous chemical barrier in the soil. Most common treatment for subterranean termites. Products: Termidor (fipronil), Premise (imidacloprid). Lasts 5-10+ years. Professional application required.

Bait stations ($1,000-$3,500 initial + $300-$500/year monitoring): Stations placed in the ground around the perimeter. Termites find the bait, consume it, and share it with the colony (eliminating the colony over time). Brands: Sentricon, Trelona ATBS. Lower chemical exposure. Requires ongoing monitoring. Slower than liquid treatment.

Fumigation (tenting) ($1,000-$3,000+ for a house): The entire structure is covered with a tent and filled with gas fumigant (Vikane/sulfuryl fluoride). Kills all termites inside the structure. Required for widespread drywood termite infestations. Must vacate the home for 2-3 days. Does not prevent reinfestation (no residual protection).

Spot treatment ($200-$1,000): Targeted treatment of a specific infestation area. Injection of liquid termiticide or foam into walls, wood, or soil. Best for: localized infestations, drywood termite colonies in accessible areas.

Prevention

Eliminate wood-to-soil contact (minimum 6 inches between wood and soil). Fix all moisture problems (leaky pipes, poor drainage, condensation). Maintain gutters and downspouts (direct water away from the foundation). Store firewood at least 20 feet from the house. Remove dead trees, stumps, and buried wood near the foundation. Annual professional termite inspection ($75-$150). Pre-treat during new construction (the most effective and affordable time).

Costs

Annual inspection: $75-$150.

Liquid barrier treatment: $500-$2,500.

Bait station system (first year): $1,000-$3,500.

Bait station monitoring (annual): $300-$500.

Fumigation (tenting): $1,000-$3,000+.

Average termite damage repair: $3,000-$8,000.