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.

Yes, you can mudjack cracked concrete, but the cracks will need to be repaired once the concrete has been leveled. If the concrete is severely cracked in multiple places, replacement may be a better option, but for less severe cracking, mudjacking is a good solution as long as cracks are correctly caulked and sealed.

A sinking foundation can be lifted, most often by installing piers to re-level and support the weight of the house. Depending on the cause and extent of the sinking, other methods to lift a foundation include underpinning and mudjacking. Consult a foundation repair pro to determine the best way to lift your sinking foundation. 

Mudjacking can be an expensive foundation repair process, but in many cases, it’s well worth the investment. This is especially true if you’re lifting a portion of sunken foundation slab back into place. In that case, mudjacking can help avoid major structural damage and even home collapse by restoring the integrity of your structure with minimally invasive procedures. Mudjacking a concrete patio, walkway, or sidewalk can be worthwhile because it removes tripping hazards and makes your outdoor area more aesthetically appealing.