What Does Termite Damage Look Like?

Termite damage is notoriously easy to miss — until it is not. Because termites eat wood from the inside out, the outer surface often looks completely normal while the interior structure is severely compromised. By the time damage becomes visible or causes a functional problem, the infestation may have been active for months or years.

Understanding what termite damage looks like at various stages — and how it differs from water damage or normal aging — helps you spot problems early and take action before repair costs escalate.

Early-Stage Termite Damage

In the early stages, termite damage is rarely visible at all. Termites consume the soft interior grain of wood while leaving the outer surface intact. The first visible signs are usually not damage directly, but rather evidence of activity: mud tubes, discarded wings, or swarmers. By the time the wood itself shows damage you can see from the outside, the infestation has usually been active for a significant period.

What Damaged Wood Looks, Sounds, and Feels Like

Hollow Sound When Tapped

One of the most reliable early indicators of termite damage is a hollow sound when you tap on wood that should be solid. Use a screwdriver handle or your knuckles to tap structural beams, door frames, baseboards, and floor joists. A deep, solid sound is normal. A hollow, papery sound suggests the interior has been consumed.

Visual Surface Changes

As damage progresses, you may notice the wood surface beginning to show changes: slight buckling or blistering, a darkened appearance, or small cracks running along the wood grain. These changes are easy to attribute to normal aging or seasonal moisture — which is why they are so often missed.

Soft Spots or Crumbling When Probed

Severely damaged wood will feel soft when pressed and may crumble or cave in when probed with a screwdriver. At this stage, the structural integrity of the affected member is likely compromised. This level of damage typically indicates a long-standing infestation.

Mazes or Galleries Inside Wood

If you break open damaged wood, you will find the characteristic termite gallery pattern — a maze of tunnels running with the grain of the wood. The tunnels may contain soil, mud, and live or dead termites. This is the most definitive visual confirmation of termite activity.

Termite Damage by Location in the Home

Crawlspace and Basement Joists

This is where termite damage is most commonly found in Missouri homes. Subterranean termites travel up through the soil and begin feeding on the lowest accessible wood — typically the floor joists and sill plates in the crawlspace or basement. Damage here is critical because these are load-bearing structural members.

Floors

Termite damage beneath floors can cause soft spots, squeaking, or slight sagging. Tile floors may develop cracks as the subfloor moves. Hardwood floors may begin to warp or buckle in localized areas even without visible moisture exposure.

Door Frames and Window Casings

Damage to door frames or window casings can cause doors and windows to stick or become difficult to open. This is commonly attributed to humidity — but if it is happening in winter when humidity is low, it warrants investigation.

Structural Beams

In severe cases, termites can cause significant damage to main structural beams. Repairs at this level are expensive and involve not just pest control but structural contractors to sister or replace damaged lumber.

Termite Damage vs. Water Damage: How to Tell

Both termite damage and water damage can cause wood to appear darkened, blistered, or soft. The key differences:

• Mud tubes present nearby strongly indicates termites, not water
• Gallery pattern inside wood — water damage does not create tunnel patterns
• Soil or debris inside damaged wood — water damage will not contain soil particles
• Location — water damage is typically near plumbing or roof leaks; termite damage follows wood-to-soil pathways

When in doubt, have a professional inspect — both problems need to be addressed, and they may coexist.

How Much Does Termite Damage Repair Cost?

This varies enormously based on what is damaged and the extent of the infestation. Minor cosmetic repairs to trim or baseboards may cost a few hundred dollars. Replacing compromised floor joists or structural beams can run from $1,500 to $5,000 or more, depending on access and the number of members involved. Extensive structural damage can cost tens of thousands to repair properly. Early treatment is always far less expensive than late treatment plus repair.