Spray Foam To Fill Void Under Concrete

Slab Void Fill with Polyurethane Foam or Concrete

You might want to fill the voids in a concrete slab for many reasons. Maybe you’re concerned about potential sinkholes, a foundation disruption, or maybe uneven flooding. Filling the voids will make the slab more level and increase its load-bearing capacity. Two good choices for void fill are polyurethane foam and concrete.

Polyurethane foam is injected into the voids through small holes drilled in the slab. The expanding foam fills the entire void space, creating a solid mass that bonds well to the concrete. A concrete mixture is also injected into the voids, but it usually requires a much larger hole to be drilled. The concrete expands as it cures, filling the entire void space.

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Causes Voids Under Concrete Slabs

There are several reasons why voids can form under concrete slabs. In some cases, the soil may settle or erode over time, which can cause voids to form. Other times, the slab’s weight may cause voids to form if the soil underneath is not compacted properly. And in other cases, tree roots can grow under the slab and cause voids to form.

Some of the causes of voids under concrete slabs are:

  •  Poorly compacted fill material
  •  Soil erosion caused by rain or runoff
  •  Weak concrete mix
  •  Sinkholes that form beneath the slab
  •  Tree roots that grow under the slab
  •  Land slippage


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How We Can Help

We specialize in slab void fill concrete with polyurethane foam or concrete to re-support and level your concrete slab to critical infrastructures such as roadways, parking garages, runways, airport terminals, and any other slab-on-grade application.

We do underground void filling foam for sinkholes and to fill voids under concrete to stop or repair any slab on grade settlement issues. We also offer scanned imaging of the subsurface to map out the underground voids before slab void filling with polyurethane foam to know exactly where to place the fill material.

Our void filling concrete solutions are non-invasive and will quickly support and level your slab. We have a wide range of concrete mix designs to choose from, depending on the application. Our skilled technicians will place the concrete mix into the voids and compact it to ensure a long-lasting repair.

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Benefits of Filling Voids under Concrete Slabs

  •  Increases the load-bearing capacity
  •  Cost-effective, providing savings on materials and labor costs
  •  Makes the slab more level and reduces the chances of uneven flooring
  •  Can improve the appearance of the slab
  •  Can stop or repair any slab on grade settlement issues
  •  Stabilizes the slab to prevent further void formation
  •  Can stop or repair any sinkhole activity beneath the slab
  •  Fills voids completely, creating a solid mass that bonds well to concrete
  •  Non-invasive and quick to install


Here's what our satisfied customers had to say about our services:

They Turn Back Time

“Their availability is timely and their workmanship accomplishes a stabilization for concrete surfaces that turns back time.”

Julie B

One Year Later

“It has been a year since you guys came out my sidewalk still looks good and has not moved. I am glad I called FoamWorks. Thanks!”

Darrell | September, 2019

Friendly and Professional

“Very friendly and professional!!! I would recommend to anyone needing this type of work done !!!!

Satisfied Customer | March 2019

Amazing Work

“Great company will do amazing work for your concrete”

Johnny W

Affordable and Effective

“Finally an affordable way to fix my cracked driveway!!”

Shannon J

Why Work With Us

We assess every situation individually to find the best solution for your needs. We have a wide range of tailored solutions specifically for you. Our skilled technicians have the experience and expertise to quickly and efficiently fill the voids under your concrete slab. Our concrete lifting services provide a cost-effective, long-lasting solution that will improve the appearance and stability of your slab.

If you have any concerns about voids under your concrete slab, please don’t hesitate to contact us. We would be happy to assess your situation and find the best solution for you.

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Have A Few More Questions?

You can fill a void under a concrete walkway by using expanding polyurethane foam. This foam will expand to fill the void and prevent any further damage.

There are many different materials that you can use to fill a void in concrete. Some of these include epoxy resin, polyurethane sealant, and concrete patching compound.

You can fill a void under a sidewalk with concrete by using a concrete patching compound. This compound will harden and provide support for the sidewalk.


Use code "FOAM10" to receive a special offer!