You have 3 Options to raise concrete slabs
CONCRETE/CEMENT slurry (concrete raising the CRC way)
POLYURETHANE foam (referred to as poly-jacking)
Concrete has been used for thousands of years in the construction industry. It is known and proven to be an inert material providing structural hardness and durability for years. No chemical materials are used during the mixing and preparation process.
Flow-able concrete slurry is pumped down vertically to raise the sunken concrete, filling the void beneath the concrete slabs. This slurry mixture solidifies to form a solid material, with properties that are similar to poured concrete, therefore, providing resistance and strength to the existing concrete.
To raise concrete with the Poly Foam, providers have to make a chemical reaction of two component parts, commonly referred to as Side A and Side B. This happens in your yard underneath the concrete in direct contact with the soil.
You can learn more about Spray Polyurethane on the EPA website:
Health Concerns about Spray Polyurethane Foam https://archive.epa.gov/epa/saferchoice/health-concerns-about-spray-polyurethane-foam.html
One of the compounds is Isocyanate, and it is classified as a potential human carcinogen. Isocyanates are known to cause cancer in animals and are listed as Toxic Substances by the EPA and OSHA. https://www.osha.gov/SLTC/isocyanates/
Read more about Poly-Jacking:
The day the work was completed a chemical fire developed in the foam. Chicago-based meat producer has filed lawsuit against construction companies. https://everchem.com/concrete-jacking-foam-fire-lawsuit/
A chemical incident shut down blocks of downtown Vancouver. https://www.cbc.ca/news/canada/british-columbia/10-lawsuits-filed-over-2010-vancouver-chemical-fire-1.1167017
“Mud-Jacking“, as the name implies, utilizes a mixture of topsoil and water (mud) which is hydraulically pumped into a hole drilled in a slab of sunken concrete. Some “mud-jackers” follow a similar process but instead use crushed limestone or other materials. These mixes will shrink as water and moisture evaporate or dissipate into the soil.
Without the bonding agent, cement, erosion would occur quicker over time. Therefore, mud-jacking is a very temporary repair.
Caution: Some mud-jackers throw a minimal amount of cement in their mixture and call the process “concrete raising like CRC.”
Buyer Beware! Their process is NOT the calibrated and automated way of concrete raising that we stand behind.