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Why Concrete Sinks: The Most Common Causes

Wondering why your home’s concrete is sinking? The culprit is likely weather erosion weakening the soil underneath. This, combined with the weight of the concrete, pulls it deeper into the ground, leading to unsightly cracks.

The consequence? A significant decrease in your property value. From jagged cracks to unevenness and sinking, all these signs point to underlying causes that harm your concrete.

Understanding and identifying these causes can help prevent further damage.

Signs of Sinking Concrete

cracked uneven concrete in front of white garage door

Don’t ignore your sunken, cracked, or uneven driveway, pool deck, or sidewalk. These aren’t just eyesores, they’re hazards waiting to cause trips and falls. Here are the red flags:

  • Cracked Concrete: Cracks could be due to soil shifting from changes in weather, water, or soil type.
  • Uneven Slabs: Slabs can move, collapse, sink, or bulge when soil is unstable. Avoid putting pressure on these to prevent further damage.
  • Hollow Sounds: A hollow sound when tapping a slab may indicate soil issues and voids beneath.
  • Water Puddles: Frequent puddles or dampness could signal soil shrinkage or settlement, preventing proper water absorption.
  • Gaps under concrete: These may appear when the underlying soil collapses or washes out, leading to concrete sinking and creating potential tripping hazards.

These signs show it’s time to lift and stabilize your concrete. If you spot any, consider hiring a professional.

Why Concrete Sinks: The Most Common Causes

Over time, the concrete structures around your home will inevitably begin to sink. Simply put, the causes of sinking concrete have to do with local weather, soil composition, the weight of the concrete itself, and just how much you use your concrete.

In specific terms, here’s why it sinks:

  • Poor soil compaction: Loose soil from construction can shift under the weight of concrete, causing sinking and cracking.
  • Soil consistency: The type of soil matters. Clay soil expands when wet and shrinks when dry, while sandy soil can wash out – both leading to concrete sinking.
  • Soil expansion: Frequent shifts in moisture and temperature can weaken and compact the soil, causing visible damage to the concrete.
  • Soil washout: Erosion underneath concrete slabs, especially in sandy soil, creates hollow spots causing concrete to sink.
  • Drought conditions: Can cause soil to shrink and become brittle, especially in areas with clay soil, leading to concrete sinking.
  • Excess rain and poor drainage: Contribute to soil washout.
  • Invasive tree roots: These can displace soil beneath concrete.
  • Excessive weight: Cars or heavy décor can compact weak soil, worsening the issue.
  • Improper concrete mixing: Poor preparation before pouring and improper mixing during construction can compromise the concrete’s durability.

How to Support and Level Sinking Concrete

PolyRenewal™ is an efficient solution for repairing damaged concrete. It’s a lightweight yet strong polyurethane foam that stabilizes, levels, and reinforces concrete slabs in just 15 minutes. Unlike temporary fixes like mudjacking, which can worsen soil compaction due to its weight, PolyRenewal™ combats soil issues without adding stress to the ground. It’s waterproof, unaffected by soil conditions, and allows quick usage of concrete areas like driveways, sidewalks, or pool decks. This non-invasive method leaves barely a trace of repair work, making it a superior choice for concrete treatment.

Our polyurethane injection process for repairing sunken concrete is efficient and simple:

  • Drill penny-sized holes in the concrete slabs.
  • Insert injection ports into the holes.
  • Inject polyurethane foam to fill voids.
  • Allow the foam to cure in 15 minutes.
  • Seal and smooth over the injection ports.

Call JES to Lift and Level Sunken Concrete!

JES concrete technician leveling concrete

If your concrete surfaces are uneven, sinking, or cracked, JES Foundation Repair has your solution. Our concrete lifting services tackle these problems head-on. Don’t let these issues be a daunting task; our professionals are ready to assist you.

At JES, we offer innovative, warranty-backed solutions to your concrete problems with skilled technicians. Reach out to us for your concrete solution today!

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    Sinking Concrete FAQs

    The unevenness or sinking of driveways can be attributed to a variety of reasons, such as soil erosion, inadequate soil compaction prior to the installation of the driveway, the natural settling of the ground over time, and problems with water runoff or drainage. These issues can create voids under the concrete, resulting in parts of the driveway sinking or cracking. It’s important to fix cracked concrete as soon as possible. 

    Cracked concrete may indicate underlying foundation problems, which should be inspected and assessed by a professional. JES Foundation Repair provides free home inspections, obligation-free estimates, no hidden costs, financing opportunities, comprehensive repair solutions, and long-term warranties for your peace of mind. Contact us today to learn more

    The process duration varies from one to three days, based on the project’s scope. Professionals aim to work swiftly to reduce any inconvenience to your property. Materials like polyurethane set rapidly, whereas concrete and mudjacking solutions require more time to harden. A JES expert can provide you with an exact schedule during a no-cost concrete evaluation.

    Michael Wilcher

    Michael Wilcher

    Michael Wilcher is the Content Lead at Groundworks, helping us to answer all of our customers biggest questions about foundation repair, basement waterproofing, crawl space encapsulation, and concrete lifting. In his free time, Michael enjoys collecting vinyl records, watching Formula 1 Racing, and reading philosophy. He holds an MPhil from the University of Cambridge.

    *Disclaimer: “Concrete leveling” means the process by which cracked, uneven concrete is stabilized, and in many cases lifted, by means of PolyRenewal™ polyurethane foam. JES Foundation Repair does not guarantee that PolyRenewal™ can make your concrete perfectly level.

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