How to Fix a Gap Under a Fence Gate: 3 Simple DIY Methods

A fence gate needs to swing freely. However, if there’s too much of a gap beneath, it defeats the whole purpose of the fence. There are several methods to fix a gap under a fence gate, and the best one for you depends on what your gate is made of and how much you can budget for the repair. Regardless, this is a fairly easy DIY that only requires a few simple steps and materials.

1. Extend the Gate

One of the easiest ways to fix a gap under a fence gate is simply to extend the gate. Depending on your budget and your gate material, there are a few different barriers you can add to your fence.

Wooden Extensions

If you have a wooden fence gate, you can use wood to extend it toward the ground. Cut pieces of wood that are the same width as your fence boards and attach them using a drill and wood screws. You can place extensions just near the gate bottom or purchase longer pieces of wood that extend along the full height of the gate for extra support and visual cohesion.

Clip-On Gap Blocker

Gate materials such as vinyl or plastic may not be able to support a wooden extension. Instead, you can purchase a pre-made fence gap blocker. Examples include a lightweight vinyl extension or a rubber flap. These can be attached at the bottom of a gate and usually come with their own installation instructions. If your gate material is hollow, you may need to use clips, adhesives, or some combination of both rather than screws.

Chicken Wire

Chicken wire is one of the most effective chain link fence gap fillers. It can be cut to size and tied directly to a chain link or hog wire fence gate using baling wire, though it can be attached to other gate materials as well. Chicken wire is a solid deterrent for digging pests, though be wary if you have dogs or other pets since sharp wire ends may cut up paws.

2. Fill and Seal the Ground

If the gap under your gate was caused by digging or erosion, you may get better results by filling and sealing it. Some sealant options include quick-drying concrete, mortar, or foam. Which option you choose will come down to your budget and personal preference. Follow these steps: 

1. Make sure the gap is completely free of debris.

2. Pour a small bag of sand into the gap and smooth it down with a trowel until flat.

3. Use water to lightly dampen the surface and flatten it again if needed.

4. Apply sealant according to the instructions on your chosen product's packaging.

5. Smooth and level your sealant with a trowel.

6. Allow your sealant to cure. This usually takes 24 to 48 hours, depending on the product.

3. Use Rocks or Gravel

An alternative fence gate gap filler option is to use loose rocks, gravel, sand, or a mixture of gravel and sand. While not as sturdy as a sealed surface, these options are cost-effective and can't be dug through as easily as dirt.

However, you’ll have to monitor and maintain your chosen fix and add additional filling over time as needed. Depending on your needs, this approach may be best as a temporary fence fix while you gather the budget and materials for more permanent repairs.

Why Do I Have Gaps Under My Fence Gate? 

There are many reasons a gap might develop under a fence gate. Some of the most common causes include: 

• Faulty installation: Measurement errors and mistakes related to the slope of the terrain can lead to gaps.

• Erosion or soil movement: The ground may shift, sink, or erode, moving gate posts or carrying away soil.

• Pets and pests: Dogs and other animals may dig under your fence, creating gaps large enough to squeeze through.

If you have a gap under your fence gate, it's worthwhile to fix it as soon as possible. Not only does a gap look bad, but it can render the entire structure useless if you use the fence for safety.

How to Prevent Gaps From Reforming

Once your fence gate gap is fixed, take the following steps to prevent new gaps from forming.

• Ensure that the gate is plumb and level, and shim the gate if needed to prevent sagging.

• Install post caps on exposed wooden gate posts to prevent rotting and shifting.

• Paint or seal the bottom edge of wooden gate extensions to reduce moisture damage.

• If you've sealed the gap, reseal it every few years to avoid the need for major repairs.

DIY vs. Hiring a Pro

The cost of fixing a gap under a fence gate depends on the DIY method you choose. No matter how you get the job done, however, you can expect to spend less than $50 on materials.

If you aren’t comfortable with the project or you’d prefer to have a pro do the work for the sake of time and efficiency, you can hire a fence and gate repair pro near you. The average cost of fence repair depends on the work being done, but you can expect to pay about $200 to have boards replaced or extended on a gate.