Polyjacking can be a permanent solution to sunken concrete if you also address the underlying issue—like poor drainage—at the same time. The polyurethane material itself can last as long as or even outlast the concrete you’re lifting it with. Your sunken concrete issue will likely return if you don’t couple polyjacking with proper drainage to prevent future soil movement and sinking.

Generally speaking, push piers—or steel piers—are the best option for underpinning, as they reach down to solid bedrock to find support for your foundation rather than relying on soil, which could be subject to the same issues as the soil directly below your foundation. However, the best underpinning method for your home depends on your location, how far down the bedrock is, and the type of soil in your area. Helical piers are usually the best option for sandy soil or in areas where the bedrock is too deep to use steel piers.

Mudjacking typically takes 24 to 72 hours (one to three days) to dry and cure completely before you can resume normal use. The exact time can vary depending on the size of the project. Because the slurry mixture contains cement, it must fully harden to ensure that added weight from walking, furniture, or vehicles won't shift the concrete slab. A professional contractor can advise you on when the surface is safe to use. For comparison, if you use polyjacking instead, the polyurethane foam can dry in just a few minutes, but it's best to wait about an hour before use.

Polyjacking and mudjacking can both be effective solutions for sinking concrete, but they have key differences. Polyjacking, which uses expanding polyurethane foam, is often considered a better option because the foam is significantly lighter than the cementitious material used for mudjacking. This reduced weight puts less pressure on the underlying soil and lowers the risk of future sinking. Polyjacking is suitable for any sinking concrete slab, while mudjacking is typically only recommended for non-structural concrete, such as sidewalks, patios, pool decks, and driveways. The primary drawback of polyjacking is its cost, which can be up to four times higher than mudjacking—as much as $25 per square foot compared to a maximum of about $6 per square foot for mudjacking.