Termites in Your Fence Posts: What It Means and How the Fence Gets Fixed

A question fence builders hear all the time

"Is this a sign of termites?" is one of the most-viewed questions among fence builders and homeowners online, usually with a photo of a post covered in dirt trails or a picket that crumbles when pressed. The answer matters, because termite damage and rot look similar from a distance but call for slightly different responses — and because a fence near the house raises a second question about the house itself.

Signs it's termites

• Mud tubes — pencil-width tunnels of soil running up the post or along the bottom rail.
• Tunnels along the grain when you break off a damaged piece, often packed with soil.
• A post that sounds hollow when tapped, even though the surface looks intact.
• Swarming winged insects or piles of shed wings near the fence in spring.

Termites or rot?

Rot tends to be soft, dark and wet, concentrated right at the ground or concrete line, with the wood breaking down into stringy or cracked pieces — see why fence posts rot at the concrete line. Termite damage is usually drier, with hollowed galleries and soil packed inside. In practice, the two often show up together, because damp, softened wood is exactly what termites prefer.

What it means for your house

A fence with termites doesn't automatically mean the house has them. But a wood fence that touches the house, or runs right up to the siding, can act as a bridge. If you find active termites in a fence near the house, have a licensed pest control company look at the structure. We repair and rebuild fences; termite treatment is a separate, licensed job.

Repair options

• Replace the affected posts. If the damage is limited to a few posts and the rails and pickets are sound, replacing posts is usually the most cost-effective repair.
• Switch to metal posts. Galvanized steel posts with wood rails and pickets are a common upgrade in termite-prone areas, because the part of the fence in the ground is no longer food. Experienced builders often point out that the posts are the first thing to fail on a wood fence.
• Keep wood off the soil. Pickets should stop above grade, and mulch, soil and irrigation spray shouldn't be piled against the fence.
• Leave a gap at the house. Ending the fence with a small gap or a non-wood connection at the wall removes the bridge.

Repair or replace the whole fence?

If termites or rot have spread through many posts and into the rails, a full replacement may be the better long-term value — see the 20 percent rule for repair vs. replace. If you're replacing anyway, it's a good time to reconsider materials; our guide to cedar vs. pine privacy fences covers the wood options.

Shared fence with a neighbor?

If the damaged section sits on a shared line, talk with your neighbor before work starts. Termites don't respect property lines, so a repair on one side alone may not solve the problem for long.

Found damage in your posts?

Call for a free consultation, or see our wood fence repair page.