A void under a patio concrete slab

Expert Void Fill Services in Alabama

Void fill is an effective solution for stabilizing sunken or shifting foundations. Learn how this process fills gaps and restores the structural integrity of your home, preventing further settlement and protecting your property from future damage.

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Overview

Void Fill: Stabilize Your Concrete, Protect Your Home

Voids beneath concrete slabs can be a hidden danger to your home’s foundation and property. These empty spaces, caused by soil erosion, poor compaction, or water, can cause concrete to sink, crack, and become unstable. Left unaddressed, voids can lead to tripping hazards, drainage issues, and even structural damage.

At SouthernDry, we provide professional void-filling services that use a specialized polyurethane foam to fill these empty spaces. This process re-supports concrete slabs and restores stability, preventing further damage and protecting your property from the ground up. The process is fast, clean, and far more cost-effective than replacing the entire slab.

Void under a concrete slab
Voids beneath your home's slab is an invitation for water damage
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  • Industry-leading warranties and guarantees

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  • A+ BBB Rating

  • Fair & Honest Pricing

  • Experience You Can Trust

  • 100% Financing available

  • Licensed, bonded, and insured

  • No Sales Games

  • Industry-leading warranties and guarantees

  • Recommended by Your Neighbors

  • A+ BBB Rating

Importance of Void Filling

Why Void Filling Isn’t Just an Option, It’s Essential

Hidden voids weaken from beneath.

Empty spaces under your concrete result from soil erosion, poor compaction, or water washout. Over time, they let slabs sink and sink again, whether under heavy vehicles on your driveway or the weight of daily use on walkways.

Unsafe surfaces don’t always look broken.

You may not see large cracks, but hollow sounds when you tap concrete, sudden dips underfoot, or puddles in unlikely spots all point to soil that’s slipping away.

Left unchecked, voids cost more than just safety.

They can lead to everyday hazards like tripping, inject instability into your foundation, and water intrusion that accelerates damage. Fixing them early prevents much bigger problems later.

Void under a concrete slab
Voids in your home's concrete invite problems with moisture, pests, and more
Warning Signs

Critical Warning Signs of Hidden Void Dangers

These seemingly minor issues indicate potentially catastrophic void problems:

Immediate Safety Threats

  • Small cracks are appearing and expanding in concrete surfaces
  • Settling or sinking sections create uneven surfaces
  • Hollow sounds when walking or tapping on concrete areas
  • Water is pooling in areas that previously drained properly
  • Rocking or movement when weight is applied to specific spots

Progressive Structural Failure

  • Widening gaps between concrete sections or along building edges
  • Door and window alignment issues indicate foundation movement
  • Stair separation from patios, sidewalks, or building structures
  • Utility line stress from shifting concrete affecting plumbing or electrical systems
  • Drainage disruption is causing water flow toward building foundations

Hidden Underground Destruction

  • Soil washout from poor drainage creates expanding cavities
  • Freeze-thaw cycles expand existing voids during the winter months
  • Root infiltration and decay create organic matter voids
  • Construction settling from inadequate initial soil compaction
  • Water line leaks gradually erode the supporting soil structure
Void Fill Process

How Our Void Fill System Works

  1. We assess the problem.
    A Certified Foundation Specialist inspects the affected area, identifying voids beneath concrete surfaces like driveways, patios, garage floors, or sidewalks. We look for signs of soil movement, washout, or poor compaction.
  2. We access the void with minimal disruption.
    Small holes, no larger than a penny, are drilled through the concrete surface at key points. This allows us to reach the hollow areas without demolition or damage to the slab itself.
  3. We inject high-density polyurethane foam.
    Our expanding foam fills the empty space beneath the concrete, compresses any loose soil, and provides immediate support. It lifts and stabilizes the slab from beneath while curing in minutes, not days.
  4. We finish and seal.
    Once the foam has cured, we seal the injection points cleanly. The result is a supported, level slab that’s ready for normal use with minimal downtime.
Benefits

Benefits of Void Filling

  • Restores Stability: Re-supports concrete slabs, preventing further sinking or cracking.
  • Prevents Structural Damage: Addresses underlying voids to protect your home’s foundation and other structures.
  • Cost-Effective: Avoids the need for costly slab replacement by repairing the issue underneath.
  • Quick and Clean: The process is fast, with minimal disruption to your property or daily routine.
  • Durable Solution: Polyurethane foam is moisture-resistant and long-lasting, ensuring a permanent fix.
Why Trust SouthernDry
Happy customer posing in front of their home after foundation repair and waterproofing services
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Why Alabama Homeowners Choose SouthernDry for Void Fill

  • Precise engineering, not guesswork—Your repair is based on expert diagnosis and custom foam delivery.
  • Fast, non-disruptive, with results you can use almost immediately.
  • Long-term reinforcement, keeping structures stable and intact for decades.
  • Backed by legacy—Your project is handled by a Certified Foundation Specialist and supported by our strong reputation and warranty philosophy.

Protect Your Property with Void Filling Today!

Voids beneath your concrete slabs won’t fix themselves, and delaying repairs can lead to bigger problems down the road. With SouthernDry’s professional void fill services, you can restore stability and extend the life of your concrete surfaces.

Contact us today for a free inspection and let us help protect your home from the ground up!

Contents

Fair & Honest Pricing

No Sales Tactics

We believe in real, honest, 100% transparent pricing. Not “price matching” gimmicks and marketing tricks like some companies.

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  • Priced with integrity

  • Built on honesty

It was an outstanding experience. The crew performed the work quickly and correctly and the price beat everyone else.

Had my house encapsulated, from the start with the sales representative to the end with the maintenance crew, it was an outstanding experience. The crew performed the work quickly and correctly and the price beat everyone else.

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Their prices were better and the results are excellent. Recommend them highly.

We had our crawlspace encapsulated and Southerndry did an excellent job. Everyone we dealt with was friendly, professional, and very competent. Their prices were better than almost all other estimates we received and the results are excellent. Recommend them highly.

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Southern Dry was not the cheapest but no where near the most expensive.

My crawlspace was wet, moldy, and just nasty. The insulation was soaking wet and it smelled awful. I called five different companies to come out and give me quotes on what they thought needed to be done. I had quotes all over the board ranging from $7,000 all the way up to $48,000. Southern dry…

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Certified Foundation Specialist smiling while reviewing an estimate

SouthernDry Financing Solutions

Easy Financing Options for Affordable Payments

Most homeowners don’t expect to deal with water in the basement or cracks in the foundation. But when these problems show up, delaying repairs can make the damage worse—and more expensive.

  • Simple Process

  • Fast Approvals

  • Multiple Financing Options

  • Today’s Best Rates

The group you sent to do the work at my house were so nice! Your installation people are what make the difference!!

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Had my house encapsulated, from the start with the sales representative to the end with the maintenance crew, it was an outstanding experience. The crew performed the work quickly and correctly and the price beat everyone else.

View Review

We had our crawlspace encapsulated and Southerndry did an excellent job. Everyone we dealt with was friendly, professional, and very competent. Their prices were better than almost all other estimates we received and the results are excellent. Recommend them highly.

View Review

My crawlspace was wet, moldy, and just nasty. The insulation was soaking wet and it smelled awful. I called five different companies to come out and give me quotes on what they thought needed to be done. I had quotes all over the board ranging from $7,000 all the way up to $48,000. Southern dry…

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Wow!! I called less than a week ago with a major moisture/mold problem under our house that we discovered. They had someone out within a few days. And not even a week after my initial phone call, they had 2 crews out working on our home. Allen- Crew 4 & Chochi- Crew 3. They had…

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Jake was Awesome! He communicated well, was on time, respected my property and was very professional. He explained everything well and even showed me pictures of my crawl space so I could see existing issues. I appreciated this because most could tell me anything and I would never know if they were just trying to…

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600+ 5-Star Reviews