Damaged Wood Expansion Seam in a Driveway

Causes

• Wood expansion joints are affordable and simple to work with, but they’re more vulnerable to rot than other materials. If the joints are not properly sealed, surface water will eventually penetrate the narrow gaps between the joints and concrete. Frequent exposure to moisture without proper air flow can cause the wood to develop mold or become waterlogged. Signs of damaged wood joints include discoloration and dislodged pieces.

Risks

• Once expansion joints begin to degrade, the driveway around the joint has no protection from water damage. Even if the surface is sealed, water will run down the exposed joints and eventually erode the dirt or sand base. This can cause the pavement to sink and crack, or if the water pools and freezes it can cause the pavement to heave. Damage to a small section will spread until it the damaged wood is removed.

Repair

• Do-it-yourselfers can repair damaged expansion seams with a few basic materials. The first step is to remove all of the damaged wood. Chip it out until the opening is wide enough to pry out larger pieces. Remove more wood than you think is necessary in case the damage is spread further than you can see on the surface. Once the entire expanse is dry and clear of debris, fill it with sand until it is about 3/4 inch from the surface. Cover the remaining hole with flexible epoxy, silicone caulk or expansion joint compound. Smooth the surface with a gloved finger to give it a clean finish, and wait a day for the compound to dry.

Maintenance

• One of the simplest ways to prevent damage to the other expansion seams is to seal them. Use a paint brush to coat each seam with transparent expansion joint sealant. Sealant repels moisture and protects the material from grease and oils stains. Plan to re-seal the joints every 2- to 3 years as regular vehicle traffic and weather wear it away over time.