A majority of homes have concrete sidewalks, patios or driveways around them. If it does, there is a good chance that this concrete has settled over time as well. This settled concrete is unsightly, takes away from the value of your home, causes water in your basement and creates potential safety hazards like pooling water and tripping hazards.
Part of determining how to repair settled concrete is understanding why the concrete settled in the first place. It is caused by a number of issues, ranging from how the concrete was constructed, soil it is sitting on, poor grading around it, poorly placed downspouts and even animal damage. Essentially concrete settles because the subgrade, the area beneath the concrete, has been compromised in one of the ways mentioned above; leaving a void that causes the settlement and often times cracks the concrete along the way.
What is the most cost effective way to repair settled concrete?
Three popular ways to repair settled concrete are to replace the concrete in its entirety, mudjack it or raise it using special polyurethane structural foam (often called Polyurethane Concrete Raising).
Replacement- Replacing the concrete is the most expensive and disruptive by far, but in some instances it may be the only course of action. For example, if the concrete has cracked so badly that it looks like a shattered piece of glass, replacement is the only option. Replacing the concrete also gives you the opportunity to update the look of your home with any number of decorative solutions, including stained and stamped designs.
Replacement requires the existing concrete surface to be removed, often times with loud jackhammers and heavy machinery. Then the sub-grade issues that caused the settlement have to be addressed, including adding stone that needs to be compacted. Once the stone is compacted, the forms for the new concrete can be put in place, village inspections completed, and the new concrete can be poured. This is not where the journey ends however. Once the concrete has a chance to cure, the forms are removed; surface sealers applied and finally the landscaping that was damaged during the replacement can be repaired. The process can take as long as a week, or longer, before you can walk or drive on the driveway again.
Mudjacking- This process has been around for about 60 years and is the least costly, but also the least permanent of the three options. The mudjacking process is pumping thick liquid slurry of material through large holes in the concrete (sometimes as large as 2” in diameter) in order to create enough pressure to hopefully lift the concrete slabs back into place.
The material used in mudjacking is really up to the company that is doing the work. It could be comprised of cement and sand, much like mortar used to build a brick wall or it could be nothing more than top soil mixed with water. Because of the nature of the materials used, it can be washed away by rain, downspout discharges or cause further settlement due to the heavy weight of the material being pumped under the concrete. This is a good option if you are looking to complete an inexpensive repair and are not concerned with the longevity of the repair.
Polyurethane Concrete Raising- This is the most cost effective way to repair settled concrete. The process is similar to mudjacking in that material is pumped through holes in the concrete surface under the concrete in order to lift it but that is where the similarities end. Polyurethane Concrete Raising has four advantages over mudjacking:
1. The material is expanding closed cell polyurethane foam, similar to material used for foundation crack repairs. This means the material will not deteriorate with water contact and because it expands, fills the entire void under the concrete.
2. The holes the material is pumped through in the surface of the concrete are only 5/8 of an inch, about the size of a dime to put it in perspective. The repair is much less intrusive or noticeable than mudjacking.
3. Polyurethane foam is a much lighter material than mudjacking slurry, minimizing additional weight being added to subgrade which could cause further settlement.
4. The material cures very quickly so driveways, sidewalks and patios can be put back into service within minutes.
As you can see there are better, more cost effective ways to repair settled concrete than just replacing it. If you have settled or uneven concrete around your home and aren’t sure how to correct it, give us a call. At U.S. Waterproofing, we have the knowledge and experience to be able to help you decide what method is best to repair settled concrete around your home. Contact us for a free consultation.