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Why Are My Fence Boards Warping?

Are your fence boards warping? Check out this article to find out why, what can be done to fix the problem and things to do to prevent warping in the future.

Back yard with dark green lawn, tall trees, sun shinung through dark brown wooden fence

Choosing the right wood for our fencing needs seems like an easy task. Yet, there’s so much that can go wrong when we use wood that isn’t the ideal choice. One of the main problems that we can encounter is warping that occurs sooner than we expected. 

As a whole, fence boards warp due to different reasons. However, the main one is moisture that gets into the fence boards, and change their composition. As a result, it’s important to follow preventative measures to ensure that we avoid any fence boards from warping. 

To learn more about what causes warping on fence boards and all the ways that we can prevent them, you’ve come to the right place.

Find out more about what tips I have to share about fence warping. 

Preventing Fence Boards From Wraping

Close up of a warped fence board that needs repair

First things first, it’s crucial for anyone to know how to prevent warping before it becomes a detrimental and expensive problem. Luckily, there are a number of things that we can use to prevent warping in our fence boards. The great news is that most if not all of these are simple and straightforward solutions.

I will summarize these in these points below. 

Buy the Right Materials

The one thing that I like about wooden materials is that they come in various types. This means that we can find the ones that don’t absorb the most water. This means that these won’t run the risk of being damaged by rainfall as much. 

These are the recommended types of wooden materials that are less likely to warp. 

  • Cedar smells great and keeps pests away while maintaining its thickness in most weather conditions. 
  • Redwood is excellent because it contains a natural chemical that prevents it from absorbing any excess moisture. Plus, it keeps warping at bay through its straight grain pattern. 
  • Fir has a much more stable equilibrium moisture content than any other type of wood that we can find. 

When we buy our wooden materials, it helps when we know the type of tree that our material was cut from. Additionally, the grain pattern will always tell us if the tree is good quality or not. So, I prefer to opt for a perpendicular grain pattern over a circular one. 

Consider Pressure Treated Wood

Ideally, we should choose wood that has the ideal amount of chemicals and preservatives. These come in handy when we wish to keep pests away, and when we live in a region with extreme weather conditions. Pressure treating our wood is what helps with keeping it from rotting. 

Naturally Evaporate the Boards of Heat Them in a Thermally Insulated Container

When we buy wood from someone, we don’t know the processes that they use to ensure that it’s dry. This is why the rule of thumb is that we should leave our wood to dry out for some time before using it for our fence boards or posts. Fortunately, when wood is pressure treated, it’s usually dried out in a thermally insulated container. 

The most important reason why we should leave our wooden boards to dry out is that they need to acclimatize with where we live. This gives us a better idea of how much drying our wood still needs while it’s outside our home. 

Use Other Materials to Protect the Wood

There are other ways that we can use to ensure that our wooden fence boards are stored to prevent warping. If we won’t be using our boards immediately, it’s a good idea to use pressure to support them while being stored. We can also place them on more solid and impermeable materials to ensure that moisture doesn’t seep through them. 

Build a Sturdy Fence

Light brown wooden fence, green grass and tall green trees, sunny day

Building a sturdy fence is the most crucial way that we can ensure that we protect our fence boards. This should help it from sagging in the long run which will inevitably lead to warping. The best tips that I recommend are the following. 

  • Using blunt nail tips. 
  • Using screws 
  • Avoid splitting by pre-drilling fence holes. 
  • Put back rails or horizontal boards. 

Use Sealant as Quickly as Possible

Once the wood has been dried properly and reaches the ideal level for its equilibrium moisture content (EMC), it’s best to seal it as quickly as possible. A pigmented sealer is a great option. It serves a functional and aesthetic purpose. 

Additionally, I always recommend that we use a sealer once every few years. This should help reverse any damage caused by UV rays while protecting our fence boards. 

How To Fix Warped Fence Boards

Now that we know how to prevent our fence boards from warping, we should know how to fix them when the inevitable occurs. Luckily, I found out that we can still salvage our warped wood. These five steps have saved me from replacing my fence boards after they had warped. 

Step 1: Apply Water to Warped Area

This is the most important step because it helps to stabilize the wood by giving it its original moisture content level. I can do this by either dampening the wood, or by submerging it in water. It usually depends on how much wood has started warping. 

Step 2: Use a Glue Mixture

Wood glue being applied to some fence boards in a shop

Adding wood glue or white glue to my water mix can help to keep my fence boards straighter for longer. The glue acts as a natural sap replacement in the warping wood. 

Step 3: Allow it to Dry

When allowing the wood to dry, applying pressure evenly throughout is recommended. It helps to ensure that the entire board is straightened. But, we shouldn’t use too much pressure because it can damage the fibers in our wood. 

This step requires patience because it can take up to a week. 

Step 4: Use Artificial Heating

Silver with black cord heating mat

Sometimes, waiting for a week can be too much. So, if we have other things to do, we can always choose to use artificial heating on our wood to speed up the process. Surprisingly, a heating blanket or a mat can do wonders when left to dry the wood for around eight hours a day. 

Step 5: Reseal the Wood

This is a crucial step to ensure that everything that’s been done is completed. The main purpose of using a sealer after drying the wood is to prevent any untimely future warping. Plus, it protects the wood from pests and rotting. 

How to Keep Fence Posts from Warping

The prolonged moisture in the soil is one of the main reasons why fence posts become damaged. When this damage becomes too much, it affects the durability of our fence. As a result, it can topple over when we least expect it. 

Since part of our fence posts are submerged underground, it can be difficult for us to notice when there’s a lot of damage and warping taking place. This is why these preventative measures are important. 

  • Ensure that the posts are dried sufficiently before being used. This can take weeks or months give or take. 
  • Add a wood preservative to the bottom part that will be in the ground. 
  • Add minus gravel to the hole where the post will be placed in. 
  • Conceal the gravel with dry soil. 
  • Wait for a couple of months before adding any wood sealer. 

Unwarp the Fence Boards

To fix the wood, we first need to follow these simple tips to unwarp the fence boards.

  1. We can use a moist towel or a soft mat to wrap the warped wood in. 

  2. When the wood in evenly covered, we should leave it for a while until the moisture is spread out evenly. 

  3. We can straighten any bent wood. Using pliers or any other tool to apply pressure works best. 

  4. Once the wood is straightened, we can start with the drying process. 
  5. Using artificial heating should be faster than leaving the wood to dry outside. 

  6. Once the wood is completely dry, we should apply a sealer to ensure that the required moisture is locked. And, to keep it protected from external factors. 

How to Fix the Picket 

Close up of distressed white picket fence with tall green and furple flower bush growing through

When it comes to the warped pickets, we have a few options. We can either repair them or replace them. However, the most convenient option to go for is replacing the pickets. 

To make our picket fence look new, these are the tips that I recommend. 

  • Prime and paint the pickets after we’ve removed the old and warped ones. 
  • Make sure the new pickets align with the old ones. 
  • Unscrew all the warped rails and paint over them.
  • Prime and paint everything again.
  • When attaching the new rails, ensure that they’re in line with the old ones.