What Is Polyurethane Foam Concrete Lifting?
Polyurethane foam injection (also called poly foam lifting or foam jacking) is the newer alternative to mudjacking for raising settled concrete slabs. Here is how it works and when it is the better choice.
The Process
Small holes (typically 5/8 inch in diameter, vs. 1.5 to 2 inches for mudjacking) are drilled through the settled slab at strategic locations above the void below. A two-component expanding polyurethane foam is injected through the holes using specialized equipment. The foam expands as the two components mix, filling the void and exerting lift pressure against the underside of the slab. The technician monitors the slab level in real time, stopping the injection when the slab has reached the target elevation. The foam cures to a rigid structure within 15 to 30 minutes. The drilled holes are patched with a color-matched concrete filler. The entire process for a standard residential application: 1 to 3 hours, with the slab ready for vehicle traffic within 1 to 2 hours of completion.
Advantages Over Mudjacking
Faster cure (15 to 30 minutes vs. several hours for mudjacking slurry). Lighter material (2 lbs per cubic foot of foam vs. 100+ lbs per cubic foot of cement-sand slurry) — important for areas near the foundation where additional weight on the fill soil is a concern. Smaller drill holes (5/8 inch vs. 1.5 to 2 inches) — less visible after patching. Ability to fill very small voids that the heavier slurry cannot reach due to viscosity. Less water in the installation process — foam injection does not introduce water beneath the slab, which mudjacking does.
When Mudjacking Is Still Preferred
Cost: mudjacking is $3 to $6 per square foot vs. $5 to $25 per square foot for polyurethane foam. For large areas (a full driveway, a large pool deck) where cost per square foot matters: mudjacking is commonly 40 to 70 percent less expensive for the same area. Polyurethane foam’s advantages are most meaningful for: areas near foundations, smaller areas with tight access, and applications where same-day use is critical.
Working With a Contractor on This Project
Getting the right outcome on any home services project starts before the work begins. A few consistent practices make the difference between a smooth project and a frustrating one.
Get at least two or three quotes. A single quote gives you no basis for comparison. Two or three quotes reveal the market rate for the work, expose scope differences between bidders, and let you assess contractor communication quality before any commitment is made. The lowest bid is not automatically the best value if the scope is thin or the materials are underspecified.
Ask for licenses and insurance before work starts. Verify current general liability insurance and, for any work involving workers on your property, workers compensation coverage. Licensing requirements vary by state and trade; confirm the specific requirements in your jurisdiction. A licensed contractor who carries appropriate insurance protects both parties if something goes wrong during the project. (For more on this, see Questions to Ask Before Hiring a Concrete Leveling Contractor.)
Get the scope in writing. A written proposal that specifies materials, labor scope, timeline, what is included (permits, cleanup, disposal), and warranty terms is the foundation of a professional engagement. Verbal agreements on any of these points invite misunderstanding. For any project over $500, written scope is non-negotiable.
Clarify the payment schedule upfront. A reasonable payment schedule ties major payments to project milestones: a deposit at signing, a payment at material delivery or project start, and a final payment at completion after a walkthrough confirms satisfaction. A contractor who requires full payment upfront before work begins is a red flag in any trade.
Making a Confident Decision
The information in this article is designed to help you ask better questions of the professionals you work with, evaluate their answers with more confidence, and understand the decisions involved in this type of home services project. It is not a substitute for professional assessment of your specific home. (For more on this, see Questions to Ask a Concrete Leveling Contractor.)
Every home is different. Roof slopes, local weather, tree exposure, soil conditions, and existing system condition all affect what the right solution is for your specific situation. The general principles here apply broadly, but a professional who assesses your home in person will give you guidance that accounts for the details that general articles cannot.
When you are ready to move forward, getting at least two or three quotes from licensed, insured, local contractors is the most important practical step. It lets you compare approaches, assess contractor quality, and confirm that the solution proposed matches your specific situation and budget.
Cost figures on this page were checked against published pricing on September 2, 2026. How we source cost data.