9 Ways to Get rid of Snakes Under a Concrete Slab

Getting rid of snakes under a concrete slab requires sealing entry points, removing food sources, and using exclusion techniques. Snakes seek shelter under concrete slabs because they offer cool, dark, moist environments with access to prey (rodents, insects). Common species include garter snakes, rat snakes, and copperheads. This guide covers 9 proven methods to remove them and prevent re-entry.

Identify How Snakes Are Getting Under the Slab

Before removing snakes, identify how they are entering. Common entry points include:

• Expansion gaps between the slab and foundation walls
• Cracks in the concrete wider than 1/4 inch
• Gaps around pipes and utility penetrations
• Deteriorated mortar in brick or block foundations
• Drainage pipes and weep holes that provide access

9 Ways to Remove Snakes Under a Concrete Slab

1. Install a one-way exclusion door. Place it over the main entry point. The snake can exit but cannot re-enter. Leave in place for 2-3 weeks.
2. Set up glue traps near entry points. Check traps daily. Release non-venomous snakes with vegetable oil. Call a professional for venomous species.
3. Use a snake trap tube. These specialized tubes trap snakes alive without harming them. Place them along walls where snakes travel.
4. Remove rodent populations. Snakes follow food sources. Eliminate mice, rats, and insects under the slab.
5. Reduce moisture. Fix leaks, improve drainage, and install a vapor barrier. Snakes need moist environments.
6. Seal all cracks and gaps. Use hydraulic cement for large cracks, expanding foam for gaps around pipes, and 1/4 inch hardware cloth for vents.
7. Install snake-proof fencing. Bury 1/4 inch galvanized hardware cloth at least 6 inches deep around the perimeter of the slab.
8. Use sulfur-based repellents. Sprinkle sulfur powder around the slab perimeter. Reapply after rain. Effectiveness is moderate.
9. Call a professional. For venomous snakes or large infestations, call a licensed wildlife control operator.

Prevention

• Seal all gaps and cracks around the slab foundation.
• Keep the area around the slab clear of debris, wood piles, and tall grass.
• Install snake-proof fencing before the next active season (spring).
• Control rodent populations around the property.
• Inspect the slab perimeter monthly for new gaps or signs of snake activity.

For more, read our snake barrier guide and snake hole identification guide.

Frequently Asked Questions

How do snakes get under a concrete slab?

Snakes enter through expansion gaps, cracks in the concrete, gaps around pipes, and weep holes. Even a gap of 1/4 inch is large enough for a young snake. Older slabs with deteriorated mortar or settlement cracks are especially vulnerable.

Can snakes damage a concrete slab?

No. Snakes cannot chew through or damage concrete. The slab itself is safe. The concern is that snakes can enter your home through gaps in the slab or foundation walls. Sealing the gaps protects your home.

Will a snake leave under the slab on its own?

Snakes may leave on their own if food becomes scarce or the area becomes too dry or hot. However, if the slab provides ideal conditions (cool, dark, moist, with prey), they may stay indefinitely. Active removal is usually necessary.

How much does it cost to seal a slab against snakes?

DIY sealing costs $50 to $200 for materials (hydraulic cement, hardware cloth, expanding foam). Professional sealing costs $200 to $600 depending on the size of the slab and the number of entry points.

The Bottom Line

Getting rid of snakes under a concrete slab requires a systematic approach: identify entry points, use exclusion doors or traps to remove existing snakes, seal all gaps, and remove food sources. The most important step is sealing the slab perimeter with 1/4 inch hardware cloth and hydraulic cement. If you have venomous snakes or a large infestation, call a professional wildlife control operator.