Fence problems

Leaning and heaving posts. Wood rots where it meets soil and moisture, and in cold climates water freezing under a footing pushes posts upward season after season. The standard guidance is to set posts deep enough that the bottom of the footing sits below your local frost line, along with the common rule of burying roughly one third of the post length. Frost depth is regional - a few inches in the far South, several feet in the upper Midwest - and your building department publishes the number for your area.

Sagging gates. Usually undersized or under-set gate posts, or missing diagonal bracing. Tightening hinges is a temporary fix; the real repair is a properly set gate post and an anti-sag brace or turnbuckle.

Warped and cupped boards. Wood moving as it dries. Some of this is normal. Rapid warping often means the wood was installed wet or was never sealed. Individual boards can be replaced cheaply, which is one of wood's genuine advantages.

Neighbor and boundary disputes. The most expensive fence problem is a fence in the wrong place. If you did not survey and your neighbor disputes the line, resolve it with a survey and a written agreement before spending money on legal escalation.