Mudjacking, also referred to as concrete raising, concrete lifting, or slabjacking, is a cost-effective alternative to removing and replacing your sunken and uneven concrete. Unfortunately, homeowners are mostly unaware of how mudjacking works and why it’s an effective option to repair concrete. Let’s go into the “classroom” and learn a little about mudjacking.
The process came about in the late 1920’s to early 1930’s as a way to repair sunken concrete on highways and fill voids underneath slabs of concrete. You can find pictures of the process in Iowa, Wisconsin, and California. It has become widely used across the US today as a cost-effective repair for sunken and uneven concrete.
When your concrete settles causing a hazard, or the sub grade of your driveway erodes causing voids or cracks, you don’t have to remove the sunken or voided concrete slabs and replace them; you can have them mudjacked.
The process requires just a few steps and some special equipment including a small mudjack pump designed to precisely pump the grout or slurry in a controlled manner. The process also requires grout and some small hand tools. Most contractors typically use a small dump truck or truck-and-trailer combo to complete their jobs. There’s a larger, more self-contained truck on the market designed to mix and pump simultaneously. Due to the higher cost of this truck, most mudjackers use the truck-and-trailer method.
Here’s how it works:
- A matrix of small holes (less than 2″) are drilled through the slab of concrete. A standard sidewalk section may require 4 holes; a slab of drive could require up to 6.
- A grout or slurry is mixed up and pumped with pressure through the holes in the concrete filling voids. As pressure builds, hydraulics take over and the slab raises up to its original level. The concrete slab is now lifted and supported by the grout pumped under it. If multiple slabs are being mudjacked, the slabs are evened at the joints and many times a new grade is established.
- The holes that were drilled are discretely patched with a concrete mix and finished off to blend and hide as much as possible.
- The concrete that has been mudjacked is now ready for use. Sidewalks can be walked on and driveways can be driven on.
The main lesson for homeowners is this: when you have a sunken sidewalk or a an uneven driveway, consider the process of mudjacking as a cost-effective concrete repair.