Compare the post with its neighbours

Sight along the run from a safe position and photograph the post against a fixed background. Is one post high, is the entire run tilted, or have only the rails dropped? Note wet ground, a nearby downspout and recent digging. Compare with last summer's photographs if available. Timing alone does not prove frost heave: winter wind can also reveal an already weakened fence.

Three different things can move
  • Post within its fixing

    Look for looseness, fracture or decay.

  • Post and footing together

    Investigate soil and footing movement.

  • Rails on a steady post

    Inspect panel connections before replacing the footing.

Separate the wood from the footing

Look at the ground line without excavating around an unstable post. Soft or broken wood above an apparently intact footing suggests decay or fracture. A firm post and footing that move together suggest a different foundation problem. Loose rails can make the fence seem wobbly even when the post remains steady. Keep people away if a panel could fall; do not use the adjoining panel as a handrail.

If the supports prove sound and damage stops at one bay, Can You Replace One Fence Panel Without Rebuilding the Fence? helps define a sensible repair boundary.

Choose a repair that survives the next thaw

Resetting calls for a site-specific footing and drainage plan, including buried-service locates before digging. There is no useful universal hole depth for every Ontario soil and fence. Ask the installer to record the post material, footing arrangement, water conditions and cause of movement. If the same run has several failed posts, compare a planned sectional rebuild with paying repeatedly to refasten panels. New boards cannot strengthen a rotten post.

Real Cedar separates fence construction into posts, rails and infill; checking those elements individually prevents confusing panel damage with post failure. Real Cedar: fence construction.

Before you finish

  • Photograph the lean from the same point.
  • Record where rainwater collects.
  • Have an unstable section secured before further investigation.