Yes, expanding foam (also known as polyurethane foam) can lift concrete. This approach, called polyjacking, involves injecting the foam rather than concrete slurry to fill voids and raise the concrete slab back into place. It’s often faster and requires smaller drill holes than traditional mudjacking, though it may come at a higher cost. Some contractors also prefer polyjacking over mudjacking for more damaged and delicate slabs.

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.

Trenching and boring are two distinct methods for installing underground utilities. Trenching involves digging a channel using equipment like an excavator, trencher, backhoe, or shovel. While it is a simpler process, it causes significant disruption to the surface, landscaping, and surrounding ecosystems.

Boring, also known as directional boring, is a less invasive alternative that uses a drill to create a tunnel for utility lines without disturbing the surface. This method is more precise and is ideal for installations that need to go underneath buildings, roads, or bodies of water. Although boring is less disruptive, it is generally more expensive than trenching.

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.