Your wood fence gives your home and yard privacy, keeps pets safe, and can itself be a thing of beauty. But your wood fence is not so beautiful—or functional—when one of the fence posts is leaning, broken, rotted, or otherwise damaged. Even worse, that non-performing wood fence post just might bring down the rest of the fence.
Replacing a wood fence post while leaving the rest of the fence intact requires some patience and surgical precision. But post replacement is a very inexpensive project that is worthwhile because it can save the rest of your fence.
Equipment / Tools
- Cordless drill
- Tape measure
- Bubble level
- Narrow shovel
- Post-hole digger
- Tarp or plastic
- Replacement wood fence post
- 2 quick set concrete, 50-pound bags
- 2 bags gravel
- Scrap two-by-fours
- 8 galvanized fence rail bracket for two-by-fours
Detach Fence From Old Post
- Inside Attachment: Go to the rail side of the fence. To loosen the fence panel, tap the fence panel upward with the hammer. Tap on the bottoms of the horizontal fence panel rails. With an assistant, lift upward and set the panel aside. Do this for the panel on the other side of the damaged post.
- Front Attachment: Go to the fence panel side of the fence. Reach to the top of the fence panel and gently tilt it downward. With an assistant, take one end for each person and move the panel aside. Repeat for the panel on the other side of the damaged post.
Unscrew Fence From Old Post
Wood fence panels may be attached to the posts either on the insides of the posts or attached directly to the front.
- Inside Attachment: Go to the rail side of the fence. Locate the metal brackets that hold the horizontal rails of the fence panel. Several screws or nails will be running through the bracket and into the fence panel. With the cordless drill or hammer, unscrew all of the screws both on the damaged post and on both of its neighboring posts.
- Front Attachment: Go to the fence panel side of the fence. Locate the screws that attach the fence panels directly to the front of the fence posts. Unscrew these screws with the cordless drill or use the hammer if these are nails. Do this for both of the fence panels on both sides of the damaged post.
Many fences with horizontal slats do not use panels. Instead, each slat is individually attached to the fence post. For these situations, simply disassemble the affected portion of the fence by removing one slat at a time. Each slat will be attached to the post using two or more nails or screws.
Remove Old Fence Post
Wearing gloves, hold the post as high as possible. Rock the post back and forth. If you can rock the post at least 90 degrees, you should be able to pull it out. Because the base of the fence post is embedded in heavy concrete, you may need help removing it.
You may need to loosen the concrete base by digging around it. With the narrow shovel, slice all the way around the base to try to sever tree or plant roots. Do not use the shovel as a lever. With the base loosened, try once again to loosen and drag the post out of its hole.
Clear Hole or Dig New Hole
When you removed the old post, the fence post hole may have partially collapsed into itself. In many cases, you can use the narrow shovel to remove the soil.
Lay down plastic or a tarp first, then put the removed soil on it. Dig a minimum of 16 to 24 inches or beyond the frost line for your area. For sandy or other soft soil, add another 12 inches to the depth. A good rule of thumb in good soil is to dig the hole to a depth equaling 1/2 of the above-ground height of the post—so for a six-foot post, dig three feet deep in good soil.
Make the hole diameter three times the post diameter. So, a 3-3/4-inch diameter post should have a hole that is roughly 11-1/4 inches.
If the hole has no gravel, add a bag or two of gravel to the bottom of the hole. If the hole already has gravel, you may only need to add one bag or the amount of gravel may be sufficient.
Set New Post in Hole
Place the new fence post in the hole. With the level, plumb the fence. Nail scrap two-by-fours as braces at the base of the post to hold it upright.
Fill Hole With Dry Concrete
Once again, check the post for plumb. Open the bag of quick-set concrete and fill the hole until the concrete is about 3 inches below the level of the ground.
Add Water to Concrete
Add clean water on top of the dry-mix concrete. Use one gallon of water per 50 pounds of concrete. Allow the concrete to cure for over one hour. Remove the wood braces. Add soil on top of the concrete.
Quick setting type concrete product instructions vary somewhat by brand. For best results, carefully follow the instructions located on the product container if they differ from steps 7 and 8.
Attach Fence to New Post
- Inside Attachment: Go to the rail side of the fence. Attach new galvanized fence rail brackets on the new fence post and on the two adjacent posts. Lift the fence panel and place into in the brackets. Secure the panel with nails or screws in all brackets.
- Front Attachment: Go to the fence panel side of the fence. Nail or screw the fence panels into place directly through the front.