Mud-jacking, also known as slab-jacking, or simply concrete raising, is a process where a slurry mixture is pumped hydraulically under a slab filling any hollow areas under it and causing it to raise back to it's original level.
How It Works:
We drill 1 1/4" holes through the slab that has sunk, approximately 2 -3' apart. We then pump a crushed-limestone slurry mixture under the slab. As the limestone is pumped under the slab, it forces the concrete to raise slowly. When we reach the desired level, we stop pumping and clean the holes out and patch them. The crushed limestone then dries hard underneath the slab and holds the slab in place.
Many times we are asked how the holes we drill will look after they are patched. While it does take a little while for the holes to cure out, they typically tend to blend in pretty well with concrete as you will see in the pictures below. Bear in mind, you are purposely looking to see the holes, but when people come to your house that is not what they are focusing on, so it usually goes unnoticed. We are also asked at times to seal cracks and joints of concrete with a rubber type of caulk; but, along with that we are often asked what it will look like. Below you will see some samples of what patched holes will look like as well as rubber caulked joints. Notice that some pictures have both patched holes and caulk.
Advantages over Replacing Concrete:
1. In most applications, the concrete can be used the same day.
2. All concrete that is raised can be used immediately unless it is a driveway. In that case it can be driven on after only one or two days.
3. Another advantage is the cost. It is normally half or less of the cost of replacement.
4. There is never any worry as to whether someone will deface the new concrete surface in some way before it has set up because you will still have your original concrete.
5. When replacing concrete, some people only replace the sections that have settled, to keep the cost down. This causes the concrete to be different colors and not to match. Mudjacking keeps all your original concrete the original color.