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Sinking Concrete Slab

The structural integrity of your Bay Area home is paramount, and the stability of concrete slabs plays a critical role in maintaining it. While concrete is a durable building material, it is not immune to damage. Sinking concrete slabs, whether they are found in your driveway, sidewalk, porch, or inside your home, are more than just a cosmetic issue. They are safety hazards and can be indicative of underlying soil problems that may potentially harm your home’s foundation if left unattended.

At Bay Area Underpinning, we understand the challenges homeowners face when dealing with sinking concrete slabs. Our specialty lies in providing comprehensive and long-lasting solutions customized to address and rectify these issues, ultimately enhancing your home’s safety and appearance. In this article, we’ll explain why sinking concrete slabs occur, how they affect your home, and how Bay Area Underpinning’s innovative concrete lifting solutions can be beneficial.

What Is a Sinking Concrete Slab?

A sinking concrete slab is a condition in which a concrete surface begins to lower unevenly, resulting in noticeable dips or cracks. Beyond detracting from your property’s aesthetics, sinking concrete slabs pose significant safety risks due to tripping hazards. These issues can manifest in various concrete structures, including:

Sinking concrete slabs may also exhibit other signs of damage, such as cracks, pitting, flaking, and staining. Early identification and prompt action are essential to prevent more extensive damage, reduce risks, and restore the functionality and beauty of the affected space. Therefore, it is crucial to contact local concrete repair professionals like Bay Area Underpinning as soon as you notice any signs of concrete damage.

What Causes a Sinking Concrete Slab?

Several common factors can lead to the sinking of concrete slabs, including:

  • Settling Soil: Over time, the soil beneath the slab naturally compacts and consolidates, causing the concrete above it to sink. This often occurs when fill dirt is used and not properly compacted, and it is more likely during periods of drought.
  • Eroding Soil: Water drainage issues, leaks, or shifting soil can erode and wash away the soil beneath the concrete, leaving it without a stable base and causing it to sink.
  • Excessive Precipitation: Saturated soil from rain, flooding, or snowmelt expands and moves, causing instability in the slab. Long-term moisture can lead to erosion and soil weakening.
  • Poor Drainage: Damaged drainage systems like gutters and downspouts can allow excess water to collect on or near the concrete, contributing to underlying soil problems.
  • Tree Roots: Growing tree roots can displace the surrounding soil, leading to slab lifting and cracking. As the roots decompose, voids in the soil can form, further contributing to sinking slabs.
  • Freeze-Thaw Cycles: Repeated freezing and thawing of the ground can cause soil expansion and contraction, leading to soil shifting and stressing the slabs.
  • Installation Problems: Mistakes during site preparation, base compaction, slab curing, and pouring can result in later sinking and cracking of concrete.

Addressing these underlying causes promptly is crucial in preventing further structural damage to your home’s foundation.

Can You Fix a Sinking Concrete Slab?

Yes, fixing a sinking concrete slab is not only possible but crucial. Early identification and repair are key, as severe damage can limit repair options. The appropriate long-term solution depends on accurately identifying and addressing the underlying cause. Simply mudjacking or filling the gap under the slab with gravel can result in continued sinking.

A comprehensive approach is vital for lasting repair and protection. A whole-home solution, addressing all underlying causes and utilizing advanced techniques and products, can guarantee optimal results and prevent future occurrences.

Bay Area Underpinning employs innovative solutions like SettleStop™ PolyRenewal™, a state-of-the-art polyurethane injection system that lifts sunken exterior concrete slabs. If your home is suffering from foundational issues, we use other methods like foundation piers, including slab foundation-specific slab piers, to permanently stabilize and potentially lift your settling foundation. Every home is unique and requires a tailored repair approach, so contact our team today for a personalized assessment.

How to Fix a Sinking Concrete Slab

When utilizing PolyRenewal™ to lift sunken concrete slabs, Bay Area Underpinning follows a precise process:

  • Inspect problematic concrete slabs.
  • Verify the need for PolyRenewal™ or other repairs.
  • Drill penny-sized holes into the affected concrete.
  • Affix installation ports in the holes.
  • Mix proprietary closed-cell polyurethane foam.
  • Inject foam under the concrete slab.
  • Allow foam to fill the void under the slab, effectively lifting the concrete.
  • Let the foam cure (approximately 15 minutes).
  • Remove injection ports.
  • Fill and smooth the drilled holes.
  • Seal cracks and joints to prevent future damage.
  • Regularly inspect and maintain the concrete slabs for lasting protection.

Bay Area Underpinning’s proprietary products are customized to address your specific issues more effectively than generic solutions, providing unparalleled quality and durability.

Why Address a Sinking Concrete Slab Now

There are several compelling reasons to have a sinking concrete slab professionally inspected and repaired promptly:

  • Safety: Uneven, sunken slabs present tripping and falling hazards, especially for seniors, small children, and individuals with mobility issues.
  • Ongoing Movement: Slabs will continue to shift and sink without proper repairs, worsening the problem over time.
  • Structural Damage: The soil problems that cause sinking slabs can also damage walls and foundations if left unaddressed.
  • Water Issues: Sinking slabs can allow water to pool and seep under foundations, leading to moisture damage, mold, and cracks. Exterior issues with pooling water include poor drainage, flooding, and attracting pests.
  • Appearance and Property Value: Cracked, uneven slabs detract from curb appeal and can deter potential buyers.

Bay Area Underpinning and our distinctive solutions are essential to fully resolve these issues. Our products offer superior, lasting results that stand out from off-the-shelf options.

Contact Bay Area Underpinning for Reliable Concrete Lifting Solutions

Don’t wait until small problems turn into expensive repairs. If you discover signs of sinking, settling, or uneven concrete slabs on your Bay Area property, contact Bay Area Underpinning for a free inspection and estimate. Our trained experts have advanced diagnostics and proprietary products to lift concrete and prevent future sinking and cracking.

The PolyRenewal™ foam injection system can quickly and precisely lift settled slabs. Additionally, our comprehensive foundation repair solutions address related foundation issues for long-lasting protection. Regardless of your home’s specific requirements, Bay Area Underpinning has superior solutions to ensure its safety, stability, and longevity.


Project costs vary depending on the size of the slab, the severity of the damage, and the repair methods used. Bay Area Underpinning offers free inspections, no-obligation estimates, transparent pricing, and various payment and financing options. Contact us today to learn more and receive an accurate cost breakdown.

Bay Area Underpinning’s PolyRenewal™ foam injection process can lift settled slabs in as little as 15 minutes. However, the total project duration depends on slab size and the extent of damage. We will provide a timeline estimate during your free inspection.

Yes, our solutions are designed to withstand diverse environmental conditions, from rain and flooding to snow and droughts, maintaining stability and durability. Our PolyRenewal™ polyurethane foam is guaranteed to never wash away or erode from underneath concrete, providing lasting support. Contact Bay Area Underpinning today to learn more and schedule a free inspection.

Related Resources

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

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2333 Courage Dr. Suite C
Fairfield, CA 94533

San Jose

1161 N Fair Oaks Ave
Sunnyvale, CA 94089