How to Fill the Gap Under a Fence to Keep Pets In (2024)

TL;DR: Most dogs dig within 6 to 12 inches of the fence line, so a gap as small as 2 to 3 inches at the bottom is enough for a small or medium dog to squeeze under. The most durable fix is burying galvanized welded wire mesh 6 to 12 inches deep with a horizontal L-shaped flare, which costs roughly $50 to $150 in materials for a typical 100-foot yard.

_Last reviewed: July 2026 · 7 min read_

You patched the gap once and the dog found a new spot within a week. That's normal — a fence line settles unevenly, and a determined digger will test every low point along the run until something gives.

Okoniq Property Hub helps you log which fence sections you've reinforced and when, so you're not guessing which repair actually held.

Why is there a gap under my fence in the first place?

Ground settling, erosion, and freeze-thaw cycles are the usual culprits, not a bad installation. Soil compresses over time, especially near downspouts or low spots where water pools after storms, and that slow shift is what opens a gap where the fence once sat flush.

If your yard has drainage problems, the gap will keep coming back no matter how many times you fill it. Heavy rain washing soil away from a fence base is the same mechanism that causes 5 signs water is undermining your foundation on a house, just smaller scale. Walk the fence line after the next storm and note which sections show fresh soil washout at the base — that's where to focus first.

Wood posts that have started to rot at the base also sink, tilting the bottom rail and opening a triangle-shaped gap at one end. Fence posts and deck posts sit in ground contact the same way, so the checks in 5 signs your deck joists are rotting underneath apply directly: push on the post at ground level, and if it flexes or feels soft, the gap is a symptom of a bigger repair.

What are the best materials to fill the gap under a fence?

Buried welded wire mesh is the most reliable fix, followed by concrete pavers, and then poured concrete for permanent problem spots. Chicken wire alone is cheap at around $20 per 50-foot roll but bends easily under a persistent digger, so it works best as a temporary patch rather than a final fix.

| Method | Cost (100 ft) | Effort | Durability | |---|---|---|---| | Buried wire mesh (L-footer) | $50–$150 | Half a day | 5+ years | | Concrete pavers or blocks | $150–$400 | 1 day | 10+ years | | Poured concrete curb | $300–$600 | 1–2 days (plus cure time) | 15+ years |

For most yards, galvanized welded wire mesh with 2×3 inch openings is the sweet spot between cost and effort. Anything smaller keeps rabbits and small dogs from squeezing through, and galvanized coating resists rust for well over a decade buried in soil.

Should I bury an L-footer or use a barrier method instead?

Bury an L-shaped wire footer if your dog digs at the fence line, and use a flush barrier like pavers if the gap is from soil erosion rather than digging. An L-footer means burying mesh vertically 6 to 12 inches, then bending the bottom 12 inches horizontally back into the yard, away from the fence. A dog that digs straight down hits the horizontal flare and can't get under it, since the wire extends into the ground they're standing on rather than just blocking the fence line itself.

If erosion is the real issue and there's no digging involved, concrete pavers or a row of buried landscape blocks set flush with the ground closes the gap without needing to dig a trench along the whole run. This is the faster fix if the fence sections aren't sagging, similar in spirit to how 5 masonry jobs you're forgetting before winter treats small masonry gaps before they widen with frost. For gaps under 2 inches with no active digging, pavers alone often solve it in an afternoon.

How do I stop pets from digging new gaps once I've filled the old one?

Extend the barrier at least 2 feet past the spot where the dog was digging, since most dogs simply try again a foot or two down the fence line. A partial fix invites a new gap right next to the old one within days, so treat the whole base of the fence as the project, not just the one hole.

Adding a visual or texture deterrent helps too — a line of large decorative rocks along the buried mesh gives the dog nothing to grip while digging, and it also signals the fix at a glance when you're checking the yard later. If the yard slopes or holds water near the fence, fix the drainage first; standing water softens soil and makes it easier to dig, which connects back to the same prevention steps covered in 5 drainage jobs you're forgetting before rainy season hits. A dry, compact base under the fence is harder to dig through in the first place.

How much does it cost to fix a dig-out gap under a fence?

A DIY fix with wire mesh runs $50 to $150 in materials for a typical 100-foot fence line, plus a half day of labor. Hiring a fence contractor for the same job typically costs $300 to $600 depending on region and how much trenching is involved, since labor is the main cost driver, not materials. For a single problem spot rather than the whole fence, expect to spend under $50 and finish in an hour or two.

FAQ

How deep do dogs dig under fences?

Most dogs dig 6 to 12 inches deep near the fence line before giving up or breaking through, which is why a buried barrier needs to go at least that deep, with 12 inches being the safer target for persistent diggers.

Will chicken wire stop a dog from digging?

Chicken wire slows down small dogs and cats but bends under sustained digging from medium or large breeds, so it works best as a short-term patch rather than a permanent fix; welded wire mesh holds up far longer.

Can I use Quikrete to fill the gap under a fence?

Yes, a poured concrete curb using a bagged mix like Quikrete works well for permanent problem spots, but it takes 24 to 48 hours to cure fully and costs more in materials and time than wire mesh or pavers.

What's the cheapest way to keep a small dog from escaping under a fence?

A row of buried concrete pavers or landscape blocks set flush with the ground is usually the cheapest fast fix, running $2 to $5 per paver, and works well when the gap comes from erosion rather than active digging.

Does an electric wire under the fence work?

A buried invisible fence wire can deter digging when paired with a training collar, but it requires an upfront system cost of $150 to $300 and consistent training, so it's typically used alongside a physical barrier rather than instead of one.

This is educational information, not construction or veterinary advice. Call a licensed fencing contractor for structural repairs and consult your vet or a certified trainer if digging behavior continues after the fence is secured.