SLAB SUPPORT
Low-pressure Subsurface Injections to Stabilize Concrete
STRUCTURAL SLAB STABILIZATION
Concrete slab cracking is often the result of inadequate support beneath the slab. Over time, underlying soils, sand, or base materials may settle, shift, or erode, creating voids that allow the slab to deflect under load. Repeated traffic or impact can then accelerate cracking and joint deterioration.
Before performing surface repairs, it is sometimes necessary to address underlying support conditions.
This process involves:
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Drilling small access holes through the slab
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Injecting structural expanding foam using a controlled, low-pressure delivery system
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Filling underlying voids to restore support beneath the slab
The expanding foam material is designed to:
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Fill void spaces
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Provide additional load support
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Reduce slab deflection
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Improve stability prior to surface repair
This method does not lift or re-level slabs. It is intended to improve support conditions beneath the existing slab.
Because underlying soil conditions can vary, low-pressure injection is designed to mitigate movement but cannot guarantee complete elimination of future movement. However, when appropriate for the conditions present, it significantly improves slab stability and enhances the longevity of surface repairs.
When More Extensive Stabilization Is Required
In situations involving significant settlement, widespread soil instability, or structural subgrade failure, more extensive high-pressure injection methods may be required.
High-pressure systems:
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Deliver material deeper into the subgrade
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Can fill larger voids
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May consolidate loose base materials
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Can be used to lift and re-level sunken slabs
These systems operate at substantially higher injection pressures and require specialized equipment.
While this service is not performed directly by our crews, we coordinate with qualified subcontractors when conditions require a higher level of structural intervention.
Integrated Repair Approach
Stabilization, when necessary, is performed prior to surface repair. Once adequate support is restored, surface defects such as cracks, joints, spalls, and transitions are repaired using Flash Floor to restore smooth, durable performance.
Addressing underlying support conditions is often critical to achieving permanent-grade repair performance.