Wooden fences can look exquisite, but their lifespan is often cut short by rotting fence posts. Exposure to elements and prolonged contact with the ground can rot and eventually collapse a fence. You can prevent your fence posts from rotting and save your fence from a silent death with just a few simple practices.
Preventing Rot in New Fences
Obviously, the approaches for preventing rot are different when you’re installing a new fence and when you’re protecting an existing fence. If you’re installing a new wooden fence, take these steps to prevent post rot.
Pick the Right Location
The surroundings of a wooden fence are very important. Plan your fence’s location in a way that it’s away from vegetation and gets ample air circulation. Plants naturally collect moisture and them leaning against or contacting your wood fence will transfer the moisture to it.
So keeping greenery as far away as possible will limit moisture exposure and good ventilation will keep the wood dry and fresh. Remember this when you’re planning the landscaping.
Choose Your Wood Wisely
The type of wood you choose for your fence posts determines how well they will hold up against elements over time. Take your time to research and figure out what’s the best rot-resistant wood for your local environment.
Cedar, acacia, redwood, and cypress are some examples of sturdy and naturally insect and rot-resistant wood types. Specifically, yellow cedar is the most long-lasting, durable, and capable of resisting decay. White cedar or black locust resist fungal growth and are perfect for marshy environments.
These woods have evolved to protect themselves from decay and tend to be expensive but will save you money in the long run.
Consider Pressure Treatment:
If you’re looking for a more economical option, consider pressure-treated wood as an alternative. Pressure-treating fence posts made from naturally rot-resistant wood are also highly recommended.
Pressure-treated lumber is infused with a blend of copper or arsenic preservatives that keeps it safe from insect damage and rotting. This wood may look “green” which indicates that it’s treated with a preservative chromated copper arsenate.
Pressurized wood is prepared by removing some air from the wood in a pressurized tank and replacing it with a preservative. It’s then sealed with an exterior product to protect it against rain and snow.
Treated posts ensure the longevity of the fence. When buying lumber, check the end tag that says the wood has been pressurized. It should either be treated to the standards of the International Code Commission (ICC), the Canadian Standards Association, or the American Wood Protection Association (AWPA).
Apply Preservative Coating
Brushing over some extra coatings at the bottom third of your post before installation can add more years to it. We recommend using a liquid wood preservative, copper naphthenate. It’s an environmentally safe wood preservative which means it’s free of arsenic and chromium and you can use it in your garden area.
Cover the bottom of the posts liberally with the preservative. If you live in an area with damp conditions and wet weather, cover the entire post with it. Application trick is: keep applying coats of copper naphthenate every hour or so until you see the wood has stopped absorbing it. Allow it to dry and then install the post in the ground.
Consider a Post-Saving Sleeve
Another way to prevent fence post rot and decay is to put them in a sleeve. It’s a heat-shrinkable outer sleeve that snugly fits at the base of the post and blocks rot and termites. This sleeve typically has an interior thermoplastic bituminous lining that seals the wood and protects against moisture.
The application of a post-saver sleeve before installation essentially creates an airtight, waterproof barrier around the post base. It’s an efficient solution and super easy to put on, too. You simply wrap the sleeve on the post base starting two inches above ground level. Heat-shrink it in place with a soft flame torch, wait a few minutes, and place it in the ground.
Put Posts in Gravel and Concrete
When installing a new fence, take care to minimize contact with the soil by putting the post in concrete and gravel rather than directly in the ground.
Using a post hole digger, dig a hole approximately twice the diameter of the fence post and down to your frost line. Fill the first three inches with gravel. The gravel base prevents contact between the post and dirt and allows quick water drainage away from the post.
Place the post in the center of the hole and fill the entire post hole with cement. As the cement dries, it will hold your post firmly in place and block moisture and insects from reaching the wood. You can dome the top, creating a little slope away from the post, to divert water away for extra protection.
Use Sheeting Between Posts and Concrete
For additional protection against rot, some homeowners use a protective material between concrete and wood to prevent moisture from getting trapped. The best material for this purpose is polyethylene sheeting or rubber membrane.
Such sheeting is waterproof and flexible. You can easily cut and fit it in the space between wooden fence posts and concrete. The sheet or rubber membrane creates a barrier and protects both materials from decay.
Other materials such as concrete backer board or asphalt-impregnated building paper are also used for this purpose and are easily available at all leading home improvement stores.
Caulk the Post Base
When anchoring a fence post in the ground, you need to make sure there’s no possible room for water to seep down and rot the wood. To do this, get an exterior acrylic latex caulk or silicone caulk to seal the space where the post meets the concrete or ground. The caulking will stick to the concrete and ensure no water passes through.
Preventing Rot in Existing Fences
Rot prevention for existing fences involves treating the part of the wood fence post above ground. Here are some routine practices you should adopt:
Apply Post-Protection Products
Other than the application of preservative chemicals and stains, there are some post-protection products on the market that limit the occurrence of rot. Visit your local hardware store, browse through, and find a post-protection sealant or protectant. Most of them are easily applied by a paintbrush like a stain.
Restain the Fence and Fence Posts
Every new fence needs to be stained. Staining makes the fence look pretty, giving a nice sheen to the natural beauty of the wood and adding another layer of protection against weather and pests. With time though, this stain wears off and will need re-application.
You can apply the stain on the posts with a brush or a roller. If you’re in a hurry, an airless sprayer will also work. Just two coats are typically sufficient to protect the fence but it’s up to your personal preferences and style.
You can also use paint to seal the surface of your fence and fence posts. There’s a detailed guide on what kind of paint you should choose on FenceGnome, read here.
Clean Regularly
A fence that is free of debris, and moisture is less likely to rot. Fences constantly endure harsh sun, insects, mud, and everything the great outdoors throws their way. They’re bound to get dirty and need regular cleaning to stay in good shape.
If you delay fence cleaning, the dirt and grass clippings stuck to the fence start holding moisture and give way to bacteria and fungi growth. Both will rot your fence posts. An easy way to clean your fence is to pressure wash it occasionally.
Alternatively, you can use a scrub brush and bucket of vinegar and baking soda mix to clean the fence and posts.
Relocate Plants
We know vines and flowers growing alongside a wooden fence look beautiful. But they are terrible for the health of a wood fence and should be planted far away from it.
If you have overhanging trees or bushes surrounding your fence, trim them regularly. Similarly, relocate any plants you can away from the fence. If plants are growing too close to the fence, they will introduce moisture to the wood and eventually lead to rotting.
Tree branches or bushes leaning against your fence can put extra strain and pressure on the posts. This may lead to early breakage or cracks in the posts, overall weakening the structure.
Inspect Routinely
Sure, you see your fence every day but inspecting it for damage is something else. Regularly examine your fence and posts to check if a piece is damaged, the wood is chipping, the paint is peeling, or if there are early signs of fungi and moss. Especially after a storm, windy days, or a heavy bout of rainfall.
All you have to do is take a walk around the border of your fence and see if you can spot any spots or damage areas. Sit down to carefully check the post bases.
Remove any posts you see that have started to rot and replace them with new ones. Because if you ignore it, rot spreads pretty fast and you will set yourself up for some expensive repairs later. You can DIY simple fence repairs or call a fencing contractor for the job.
Keep Debris Away
Grass, plants, damp leaves, etc., build up moist debris that makes the most perfect breeding ground for termites and all kinds of nasty insects. Such organic debris, combined with dirt and soil, clumps up against the fence when it’s not cleaned regularly. It then enters the wood through little crevices and cracks it can find and wreaks havoc.
The best way to save your fence from rotting by debris is to keep the fence clear of plant life and grime.
Protection Against Dry Rot
When you think of rotting wood, you imagine the wood has been exposed to wet conditions. But rot can also come from exposure to harsh and dry environments. Burning sun and hot winds can dry out the wood and strip protective oils from its surface, leaving the fence weak.
You can identify dry rot if your fence posts are brittle, chipping, and easily broken. Protect them by regularly applying a protective sealant or stain on the wood. Also, make your wood fence more secure by following these tips.
Final Word
Cleaning, repairing, and taking care of a fence gets tiresome. Share your burden and call in a local fencing pro to help you maintain your fence and keep its posts from rotting and decaying.
Main Image Credit: Justin Smith / Canva Pro / License
