Concrete Void Filling in St. Louis, MO
Are Empty Spaces Forming Beneath Your Concrete?
Concrete needs solid support underneath it. When soil settles, washes away, or shifts, empty spaces can develop beneath a slab. Those voids may leave sections of concrete unsupported and increase the chance of future settlement.
St. Louis Mudjacking provides concrete void filling using a grout-based material pumped beneath the slab. The material helps fill unsupported areas and restore support beneath concrete that may otherwise continue to move.
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Why Do Voids Form Beneath Concrete?
Voids usually develop when the soil beneath a concrete slab changes over time.
Water, poor compaction, soil movement, and erosion can all remove or reduce support beneath the concrete.
Common causes include:
- Water washout that carries soil away from beneath the slab
- Poorly compacted fill that settles after construction
- Clay soil movement as moisture levels rise and fall
- Drainage problems that direct water beneath concrete
- Soil erosion along slab edges or nearby landscaping
- Freeze-thaw cycles that contribute to ground movement
- Plumbing or water leaks that disturb supporting soil
- Natural soil settlement beneath older concrete
These conditions are common around St. Louis, where clay-heavy soil and changing moisture levels can affect the ground beneath driveways, sidewalks, patios, garage floors, and other slabs.
Voids often occur alongside concrete settlement. Depending on the area affected, related services may include Concrete Slab Lifting, Driveway Leveling, or Garage Floor Lifting.
Signs You May Have Voids Beneath Your Concrete
You cannot always see what is happening underneath a slab, but there are warning signs that support may be missing.
Watch for:
- Concrete that sounds hollow when tapped
- Sections of concrete beginning to sink
- Gaps opening beneath slab edges
- Soil washing away next to the concrete
- Cracks that appear as sections lose support
- Water disappearing beneath slab edges
- Uneven areas developing over time
- Concrete that moves or rocks under weight
- Visible erosion around driveways, patios, or sidewalks
A void does not always mean the slab needs to be replaced. If the concrete is still in usable condition, filling the unsupported space may help restore support beneath it.
Our 3-Step Mudjacking Process
How Concrete Void Filling Works
Void filling uses a straightforward process to place material beneath unsupported concrete and restore support where soil has been lost or settled.
Drill & Prepare
Access holes are drilled through the slab in locations that allow us to reach the empty spaces beneath the concrete.
Pump & Fill
A grout-based mudjacking mixture is pumped beneath the slab. The material spreads into unsupported areas and fills spaces where soil support is missing.
Patch & Finish
Once the voids have been filled, the access holes are patched and the work area is cleaned up.
Learn more about the method on our Concrete Lifting & Mudjacking page.
Benefits of Filling Voids Beneath Concrete
When empty spaces develop beneath a slab, filling them can help address the lack of support before the problem becomes more noticeable.
- Restore support beneath unsupported sections of concrete
- Fill empty spaces caused by soil settlement or washout
- Help reduce future movement where support has been lost
- Protect usable concrete that may not need replacement
- Address hidden problems beneath slabs before settlement becomes more severe
- Reduce disruption compared with removing and replacing concrete
- Support nearby lifted slabs as part of a mudjacking repair
- Improve stability beneath driveways, sidewalks, patios, and other concrete areas
Void filling does not repair concrete that is badly broken or deteriorated. The condition of the slab and the cause of the void both matter when deciding whether filling the area is the right approach.
Why Choose St. Louis Mudjacking?
We keep concrete lifting straightforward.
St. Louis Mudjacking is A Nick Gress Foundations Company, bringing hands-on experience with concrete, foundations, soil movement, and the conditions that affect properties throughout the St. Louis area.
When we look at your driveway, we will explain what we see and whether lifting makes sense.
You can expect:
- Local St. Louis-area service
- Traditional mudjacking methods
- Residential and commercial concrete experience
- Careful, controlled lifting
- Straightforward recommendations
- No unnecessary replacement recommendation when the slab can reasonably be saved
Not every driveway should be lifted. If the concrete is badly broken or deteriorated, replacement may be the better answer. We would rather tell you that upfront.
Void Filling FAQs
Frequently Asked Questions
Concrete void filling is the process of placing material beneath a slab to fill empty spaces where the supporting soil has settled, eroded, or washed away.
Common signs include hollow-sounding concrete, visible gaps beneath slab edges, sinking sections, erosion, cracking, or movement under weight. In some cases, the void is not obvious until settlement begins.
We use a grout-based mudjacking mixture that can be pumped beneath the slab to fill unsupported areas.
In some situations, the same mudjacking material used to fill a void can also be used to carefully lift settled concrete. Whether lifting is appropriate depends on the slab and the condition underneath it.
Voids can develop beneath driveways, sidewalks, patios, garage floors, porches, pool decks, concrete slabs, and commercial concrete areas.
Poor drainage, heavy rain, runoff, leaking water lines, and erosion can all move soil away from beneath a slab.
It depends on the size of the unsupported area and the condition of the slab. If support has been lost, addressing the void may help reduce the chance of additional movement.
Not always. If the slab is badly broken, crumbling, or structurally damaged, replacement may make more sense than filling the area underneath it.
No. We provide void filling and mudjacking for both residential and commercial concrete throughout the St. Louis area.
Call St. Louis Mudjacking or submit a quote request. Tell us what you are seeing, and we can help determine the next step.
Have Unsupported Concrete or Suspect a Void?
If you notice sinking concrete, hollow areas, washout, or gaps beneath a slab, it is worth finding out what is happening underneath.
St. Louis Mudjacking can help determine whether void filling or concrete lifting makes sense for the existing slab and give you a straightforward recommendation.
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PROUDLY SERVING THE ST. LOUIS AREA
Mudjacking Across St. Louis County
We help homeowners, businesses, property managers, and organizations throughout the St. Louis metro area fix sinking and uneven concrete.
Our service area includes communities across St. Louis County, St. Charles County, and surrounding areas.
Areas We Serve Include:
- Chesterfield
- St. Charles
- Ballwin
- O’Fallon
- Florissant
- Kirkwood
- Wildwood
- Creve Coeur
- Maryland Heights
- St. Peters
- Wentzville
- Webster Groves
- Fenton
- Clayton
- University City
- Manchester
- Des Peres
- Ladue
- Frontenac
- Lake St. Louis
- Eureka
- Cottleville
- Brentwood
- Hazelwood
- Bridgeton
- Ferguson
- St. Ann
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A Nick Gress Foundations Company
Uneven concrete does not get better on its own. St. Louis Mudjacking helps homeowners, businesses, property managers, and municipalities lift and level settled concrete using proven mudjacking methods.
Mudjacking and concrete leveling services throughout the St. Louis metro and St. Charles County, including:
Chesterfield, St. Charles, Ballwin, O’Fallon, Florissant, Kirkwood, Wildwood, Creve Coeur and surrounding communities.
Need an estimate? Call us today.
Residential Services
Commercial Services
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Have a sinking driveway, uneven sidewalk, settled patio, or another concrete problem?
Call St. Louis Mudjacking and tell us what is going on. We will help you determine the next step.
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