The last thing you want is for your property to look disheveled or in disrepair. So when your fence starts leaning, you want to know why. You’re not the only one. Many homeowners wonder what causes a leaning fence, and there are many possible reasons. So which one’s causing your problem?
We’ll review the main causes of a leaning fence, so you can prevent your fence from looking like the Leaning Tower of Pisa. If you move quickly enough, you’ll have to repair only the fence rather than replace it.
11 Causes of a Leaning Fence
1. Rain and Flooding
Let’s skip the weather small talk. Heavy rain and flooding can shift your fence posts. How? The moisture loosens or moves the soil that your fence posts rest in, making them unstable. Excessive irrigation can have the same negative effect.
- Solution: If the water source is from irrigation, move your sprinklers or redirect the water elsewhere. To make your fence more flood-resistant, set the posts in concrete. You may need to set them deeper as well — one-third of the total post height is ideal. A slight slope on the concrete footing away from the fence will help water run off instead of pooling, but make sure the post is straight.
Certain materials are also adversely affected by moisture. Water can cause wood to swell and shrink, making it looser. Excess moisture also could make the wood rot prematurely. If you don’t regularly maintain your wooden fence, it’s more likely to lean over time. Metal fences will rust if not adequately protected from moisture, making them weaker and prone to lean.
- Solution: The tips above apply here; redirect the water and use a sloped concrete fence footing. Apply stain, paint, or sealant to protect wooden fences from the elements. Coat and regularly inspect metal fences for scratches that could let water in. If you need to build a new fence, use rot-resistant or treated wood, vinyl, or coated metal for a longer lifespan.
2. Snow
It’s not just liquid pushing your fence around. Heavy snowfall can weigh down your fence. Privacy fencing is especially vulnerable to heavy snow. Since the snow can’t pass through, all the weight will press against the side of the fence. The weight of snow also can cause branches to press into or fall onto fences, compromising their structural integrity.
- Solution: Regularly clear away snow piles along your fence and on nearby branches. You may need to set your fence posts deeper to make the barrier more sturdy. You also could replace your privacy fence with a different style that is stronger (like masonry) or allows snow to pass through (such as picket fencing).
3. Extreme Temperature Shifts
Heat and humidity can make certain fence materials like wood expand. The fence will warp and eventually lean if there isn’t room for this expansion.
- Solution: Replace warped fence pieces and apply stains to protect wooden fences. Weatherproof your fence with stain or paint. Replace with a well-suited fence type for warm climates, such as vinyl and aluminum. If you do prefer wood, red cedar is the best type to withstand extreme temperatures.
Extremely cold temperatures also can cause problems. Wood shrinks in winter, which can loosen fastenings like nails and screws.
Vinyl can become fragile and brittle during prolonged cold periods, though many manufacturers nowadays design them to withstand extreme temperatures. Check for cracks to see if this is causing your vinyl fence to lean.
- Solution: Check and replace loose nails and screws. Replace your existing fence with a type well-suited for cold climates, such as steel or aluminum. Cedar, redwood, cypress, and treated pine are the best types of wood fencing for cold. Vinyl fences with anti-impact inhibitors are less likely to crack, even in extreme situations.
What if it’s not your fence that’s the problem? Soil also can expand and contract with changing temperatures, loosening fence posts.
- Solution: Adjust the soil around the post with a shovel. If that doesn’t work, backfill the fence post to secure it.
4. Wind
One of the benefits of a fence is wind protection, but what if there’s too much wind? Strong winds can tilt or even break your barrier if it’s not sturdy enough. While vinyl is often strong enough to stand up to wind, it could warp if the gusts are too powerful. Check your fence after a storm to see how it holds up to high winds.
- Solution: Replace your existing posts with metal or concrete. Use concrete footers that are at least 30 inches into the ground. You also can use stakes, brackets, and hurricane straps to reinforce your fence. The best materials for a wind-resistant fence are chain-link, vinyl, metal, and wood. Choose a design with gaps to allow wind to pass through.
5. Tree Roots and Branches
As if the weather wasn’t enough, your trees could also be causing your leaning fence. The roots could push the fence posts or panels out of place. Branches also could shove above-ground parts of the barrier, slowly warping them. A bad storm or sickly tree could drop a branch directly onto your fence, knocking it out of place.
- Solution: Move the fence or the tree, so they’re no longer touching. You can also prune back branches or cut the roots away from the posts. If it’s going to be challenging to work around, consider whether you want that tree. If the tree belongs to a neighbor, you’ll need to discuss it with them and check your legal rights. You also should check if your homeowners’ insurance covers tree damage.
6. Sloped Terrain
A slight slope may not be visible, but it could slowly pull your fence down. It’s more important that posts are straight up and down gravity-wise rather than at a 90-degree angle with the ground.
- Solution: Re-set the posts so they’re straight up and down. You also may need to install a racked, straight, or stepped fence to accommodate the slope. You could grade or level the area if the slope isn’t too extreme.
7. Warped or Bent Materials
We already discussed how moisture and temperature could cause certain materials to warp. Pine and low-quality oak are particularly susceptible to warping. Vinyl can warp under extreme temperatures or winds.
Some materials also can become warped by impact or pressure. For example, a chain-link fence can become warped by weather, animals, people, or machinery. Metal fences are most prone to this issue.
- Solution: Stain, treat, or paint wooden fences to protect them from the elements. Pressure-treated wood and cypress are more resistant to warping, though it’s not immune. If your fence was bent out of shape by an external force, then you’ll need to replace the warped pieces.
8. Rotting Posts
If your fence is made of natural materials like wood or bamboo, it could rot. Rotted posts will cause fences to lean. Excessive moisture speeds up this process, especially if the wood or bamboo is untreated.
- Solution: Apply stains or paints every couple of years. Direct any water away from fence posts to prevent underground rot. Pressure-treated wood takes longer to rot than regular wood, so it’s worth the extra cost. Fit post-saver sleeves around the fence posts for additional protection. If you want to avoid rot altogether, install vinyl, composite, metal, or masonry fencing.
9. Pest Damage
Maybe your wooden fence is under attack from wood-destroying pests like termites or carpenter ants. Look for holes and piles of wood shavings, especially around the base of the fence.
- Solution: Get rid of the termites first (either on your own or hire a pest control pro). Replace any posts, panels, or pickets that are damaged. Stain your fence or use treated wood to prevent this from happening again. Raise untreated wood off the ground, improve drainage, reduce moisture in the area, and create physical barriers to deter pest activity.
10. Animals
What if a bigger creature is the culprit? Digging dogs or wild animals can threaten the structural integrity of your fence. If your dog or any other large animal tries to climb the fence repeatedly, it could start to lean or crack. Or wild animals might be trying to enter your yard to get into your garden.
- Solution: To prevent digging, put a concrete base along the bottom of the fence or place bricks, stones, plants, or other obstacles. A taller fence could stop some animals from jumping on or hanging off the fence. A privacy fence or screen attached to an existing fence could make your dog less inclined to escape by blocking out distractions like other dogs, animals, or humans.
11. Poor Installation
Sometimes external factors aren’t the culprit. If the fence isn’t installed correctly, it’s much more likely to lean over time. The most significant issues are shallow posts, poor-quality fence footings, and crooked or uneven installation.
- Solution: Re-set the posts in concrete. Each hole’s depth should be one-third the height of the post.
Fixing Your Fence vs. Replacing Your Fence
If your fence is leaning at all, it’s probably time to fix it. However, the severity of the issue can vary. Some problems are quick fixes, while others may require extensive work or professional help.
However, sometimes a fence is beyond repair. Poor-quality materials and extensive damage aren’t easy fixes and could cost more in the long run. In that case, you’ll need to rip it out and replace it with a new fence. Now that you know what caused your old fence to lean, you should be able to avoid those problems.
How do you know when to repair and when to replace? If most of the materials are in good condition, you likely don’t need a new fence. Just replace the damaged post, panel, or picket. A good rule of thumb is to replace your fence if more than 20% of it is damaged.
FAQ About Leaning Fences
Proper installation will stop many problems before they begin. Once the fence is installed, keep a watchful eye on the fence posts and complete the necessary maintenance and repairs. Make a note of external factors such as animals, trees, and snowdrifts that could push the fence, and make a plan to address them.
Depending on the severity of the damage, it could cost between $13 to $1,207 to fix a leaning fence. The repair will be cheapest and easiest when you only need to prop up one post. However, it could be expensive if multiple posts and fence parts need repair or replacement.
Does your fence seem like a lost cause? It costs between $1,330 and $5,550 to replace an entire fence.
Yes. Paint and stain reduce moisture absorption, lessening the wood’s expansion and contraction. It will also prevent rotting and deter termites.
When to Hire a Pro
If you’re not an experienced DIYer, you could accidentally make the problem worse by trying to repair it. Contact a fence company to straighten things out with confidence. A fence contractor near you can identify the issue and implement the right solution. Get a quote to start on your home improvement project.
Main Image Credit: CAJC: in the PNW / Flickr / CC BY-SA 2.0
