Termite damage often goes unnoticed for years. Here's what it actually looks like in walls, floors, and framing — and what you'll pay to repair it if left untreated.
Why Termite Damage Is Found Late
Termites don't eat from the outside in — they work from inside the wood outward. By the time damage is visible on the surface, the interior has often been compromised for months or years. This is why homeowners frequently discover significant termite damage during renovations or a professional inspection, having had no idea a problem existed.
Understanding what to look for — and where — gives you a fighting chance of catching damage before it reaches the structural stage.
What Termite Damage Looks Like by Location
Attic Framing
Drywood termites frequently infest attic framing. The damage: rafters, purlins, and collar ties develop smooth internal galleries that are invisible from below. The wood may look perfectly intact from the outside while being completely hollow inside.
How to identify it: During a professional inspection, the inspector will probe and sound the framing. A hollow sound when tapping a rafter that appears solid is a red flag. In more advanced cases, the wood crumbles or collapses under light pressure.
Floor Joists and Subfloor
Subterranean termites target floor joists from below — they enter through the crawlspace or subarea and consume wood along the grain. The result is a honeycomb-like structure where the joist still appears to have its original shape from the exterior but has no structural integrity.
How to identify it: Spongy or bouncy floors — especially near bathrooms, kitchens, or laundry areas where moisture is higher — are the most common homeowner-detectable sign. A professional inspector in the subarea will find mud-filled galleries and destroyed joist sections.
Exterior Eaves and Fascia
The eaves and fascia are among the most commonly infested areas in Southern California homes. Drywood termites enter through paint cracks, exposed end grain, and gaps in the fascia board. Damage progresses from the paint surface inward.
How to identify it: Bubbling or peeling paint on eaves (not associated with water damage), a soft or crumbling feel when pressing on the wood, and frass piles on the ground below the eave. In advanced cases, the fascia board is visibly crumbling or has collapsed sections.
Wall Voids
Both species can damage wall framing. Drywood termites enter through exterior penetrations and consume studs and top/bottom plates from inside. Subterranean termites travel up from the subarea through wall cavities.
How to identify it: Blistering paint that looks exactly like a small water leak behind the wall (but there's no plumbing there), a hollow sound when knocking on drywall in suspect areas, and frass piles appearing at the base of walls. Wall void damage is very difficult to assess without opening the wall.
Cosmetic vs Structural Damage
Not all termite damage is structural. Understanding the distinction affects both urgency and cost.
Cosmetic damage affects non-load-bearing wood: trim boards, fascia, decorative elements, interior wood paneling, and furniture. This is still real damage, but it doesn't affect the structural integrity of the home. Repair is relatively straightforward — remove and replace the damaged sections.
Structural damage affects load-bearing members: rafters, ridge boards, floor joists, rim joists, wall studs in load-bearing walls, posts, and beams. This requires a general contractor and potentially a structural engineer assessment before repair.
Termite Damage Repair Cost Ranges
| Damage Type | Typical Repair Cost |
|---|---|
| Minor fascia/eave replacement (cosmetic) | $300 – $800 |
| Exterior fascia + soffit replacement (moderate) | $500 – $1,500 |
| Single floor joist sistering or replacement | $500 – $1,500 |
| Multiple floor joists + subfloor | $1,500 – $4,000 |
| Structural beam or post replacement | $2,000 – $8,000 |
| Major structural damage (multiple areas) | $8,000 – $25,000+ |
These ranges reflect Southern California labor rates in 2026. Costs vary by location within SoCal (OC and LA are typically higher than Inland Empire), accessibility, and extent.
How Long Termites Take to Cause Serious Damage
Subterranean termites are the fastest. A large Reticulitermes colony (millions of workers) can destroy a floor joist in 3–5 years under favorable conditions. Major structural damage can accumulate in 5–8 years of unchecked infestation.
Drywood termites are slower. A single colony might take 5–10 years to cause significant structural damage. However, multiple colonies in the same structure (common in older SoCal homes) can cause significant collective damage more quickly.
Insurance Doesn't Cover It
Homeowners insurance categorically excludes termite damage. Termite damage is considered preventable maintenance — all repair costs are 100% out of pocket.
The Financial Case for Early Detection
The cost difference between catching termites early versus late is dramatic:
- Year 1: spot treatment $400 + no structural damage = $400 total
- Year 5 untreated: fumigation $2,500 + floor joist repair $2,000 + fascia repair $800 = $5,300 total
- Year 8 untreated: fumigation $2,500 + major structural work $15,000 = $17,500+ total
Annual inspections are free. The cost of not inspecting is real.
Related: Termite Damage Information · Termite Treatment Cost · Drywood Termites