Repairing a Broken Fence Post

A wood fence on a grass lawn.
What You'll Need
Sledge hammer
Galvanized nails
Exterior caulk
Reciprocating saw
New post

Nearly all products made from wood are high maintenance, and that means constant upkeep and repair. Wooden fence posts fall into that category. This means occasionally posts need to be repaired or replaced.

Typically repairing a wooden fence post means replacing it, but whether you repair or replace a fence post, it's a straightforward do-it-yourself project.

Repair or Replace?

The decision to repair or replace is easily determined by the kind and level of damage. Since fence posts support the fence itself, if there is any doubt about the posts integrity, it should be replaced. However, minor damage such as a leaning, shrinking, or wobbling can be repaired. This will also help prevent further deterioration.

Leveling a Post

Repairing a leaning post requires detaching the existing fence from the offending post and digging around it to reach the bottom of the post. Most fence posts are set in a concrete footing to provide strength and support for the fence. So after digging up the leaning post, break up the old footing with a sledge hammer, and remove the old the concrete.

Reset the post in the ground, making sure to that it is level, plumb (vertically level), and square to the fence. It is helpful to the brace the post temporarily to keep it level and plumb while you pour a new concrete footing. Once the footing has set, reattach the fence using new galvanized nails.

Correcting a Wobbly Post

If your fence post is wobbly, it may be from shrinking inside the concrete footing. As long as the integrity of the footing is good, a short term solution may be to shim the bottom of the post all the way around and caulk the shims in place using exterior silicon type caulking.

Where there is no concrete footing around the original post, another solution to the wobbling post is to use what is called a sister post. A sister post is a thinner post of the same width as the existing post. Drive it into the ground next to the existing post to a depth of a couple of feet or more. Bolt together the two posts to provide support. Of course, you could simply dig an appropriate hole around the original post and pour a concrete footing.

Replacing a Post

Frequently wood fence posts rot below the ground (in the footing). Something like this will leave you with no choice but to replace the post with a new one. In fact, if you have any doubt about the integrity of a fence post, the best thing to do is simply replace it. The process is the same as it is for a leaning fence post.

Separate the fence from the post to be replaced, then dig up the old post removing it and the old concrete footing. Place the new fence post in the existing hole and pour a new concrete footing. Keep in mind, it is always a good idea to temporarily brace the new post to keep it level and plumb while the new footing cures. After the footing has setup and cured, you can then reattach the fence remembering to use new nails.

A second solution, which usually does not require detaching the existing fence, is to place a new shorter post next to the rotting post. Dig around the rotten post and cut it just above the rotten point with a reciprocating saw, so as to be able to pull it out of the ground. Then place a new second post in the hole, bolting the posts together. Making sure they are plumb, and then pour a new concrete footing to hold the second shorter post. Again, it is always a good idea to temporarily brace the new post while the footing cures.

The beauty of a wooden fence is unmistakable and regular sealing of your fence either with a good water sealer or paint helps to protect it. However, regardless of your vigilance, a wooden fence is a high-maintenance product that will require regular repair. Repairing a wooden fence post, however, repairing or replacing a post is a straightforward do-it-yourself project.