Over time, wooden fence posts can start to rot and deteriorate due to prolonged exposure to moisture from the surrounding soil. As these posts lose their structural integrity, fences can collapse, and posts may need replacing. As one of the most experienced and reputable fence companies in Philadelphia, PA, we’ve created this blog to provide actionable tips to protect your fence posts from rotting:
Choose Rot Resistant Wood
Fighting back against wood rot begins with the type of wood you choose for your fencing project. Some species of wood are naturally resistant to rotting and have evolved to protect themselves from decay. Some examples of rot-resistant wood include cedar, redwood, and mulberry strains.
While these species of wood have been shown to be more resilient at fighting back against the signs of decay, they can also be expensive and difficult to work with. If you’re looking for a more affordable way to prevent your wood from rotting, you might want to consider pressure-treated wood as an alternative. Pressure-treated wood has been infused with a blend of copper or arsenic preservative to help keep it from rotting or being destroyed by insects.
Pressurized wood is created by placing the wood in a pressurized tank that removes some of the air and replaces it with a preservative. The wood is then sealed with a product designed for exterior use, which further protects it from the damaging effects of rain and snow. Pressurized wood can provide you with a mixture of affordability and strength when installing your fencing.
Dry the Fence Posts Out
Drying is an essential factor when it comes to avoiding rot. This is especially vital if fence posts have been made from green wood, as the moisture inside the wood can encourage rot. Also, moist wood isn’t as good at absorbing liquid wood preservative as dry wood. If your posts are made from fresh wood, the drying process could take several months.
Consider Adding Posts to Concrete
If your post needs support anchoring in the ground, you can bury its base in concrete. First, dig a hole in the ground about 1/4th as deep as the post itself. Using a post-hole digger instead of a shovel to create your anchor hole is more effective, as it makes the perfect size anchor point.
From here, you should fill the hole with about 6 inches of gravel. This will prevent rotting by ensuring that the post is kept dry when water makes its way into the soil. Place the post in the gravel, then fill with a batch of cement until it reaches the top of the hole.
Apply Preservative to the Wooden Post
We recommend brushing over the bottom third of the fence post with copper naphthenate. This wood preservative is free of chromium and arsenic, meaning that it’s environmentally safe to use in your garden area. Apply the preservative liberally, even covering the entire post if you live in a region prone to wet weather and damp conditions. Keep applying fresh coats of copper naphthenate every hour until the wood stops absorbing the preservative.
Dig a hole at least twice the fence post’s diameter and between 24-48 inches deep. Posts are best positioned to stand upright if one-third of the total post length is buried. However, if you are unable to dig this deep, a minimum of 24 inches is acceptable. You should leave a portion of the treated wood exposed above ground.
Fill Up the Hole
Next, fill the hole with about 6 inches of fine gravel for tight compaction. Use a level base to pack the gravel tightly around the post. Set the post in the hole using a level to ensure that it stands straight, and fill the area surrounding the post with more ¼ minus gravel. Cover the gravel with soil to conceal it, building the earth at a slight slope to encourage drainage and prevent water from gathering at the base of the post.
Finally, cut the top of the fence posts to their desired height with a saw. Cut at an angle so that any water runs off the tops without absorbing into the wood. Brush more preservative into any cracks that appear on the top of the fence posts and then apply the sealer to all of the exposed wood to enhance protection.