Epoxy injection is a resin based sealer that is forced into cracks within concrete to protect the rebar from becoming damaged, and to stop water from pooling into the foundation. Cracks and weak rebar will cause the concrete foundation to weaken, which will make the building affected unsafe for occupancy. The epoxy that is injected into the cracks effectively seals them while allowing the concrete foundations to retain their original strength and integrity. Epoxy injection repairs are the only way to fix a cracked foundation without having to tear the building down and re-pour the concrete.
The process involved in the epoxy resin process is precise and has to be done with an epoxy that is rated at least Grade A Type A for most applications. In order to effectively repair the crack, and to shield the rebar from premature deterioration, only the best products are used. The majority of epoxy injection repairs are done with injection machines or guns that are set at a air level suitable for the given application. There are maximum and minimum settings that are recommended, so all tools have to be adjusted before beginning each specific job.
Drilling ports is one of the most important first steps involved in epoxy injection repairs. Ports are drilled directly above the cracks with vacuum supported drills installed with hollow concrete drill bits. The ports allow the epoxy resin to flow down the entire length of the crack, and the vacuum support allows all of the concrete dust to be removed from the hole being drilled. Epoxy resin will form into a paste if the cement particles are not removed, which will cause the epoxy injection repair to fail, so vacuum support systems have to be used.
The ports are strategically placed every four to eight inches (10.16 – 20.32 cm) apart to allow complete filling of the cracks within the cement. The epoxy injection process begins in one port, and as the next port begins to fill with the resin the original port will be capped off. From there, the process will begin again from the second port. This process continues all the way across and down the cement foundation until the entire area has been injected with the epoxy filler.
The epoxy injection process can be performed in any weather and environment as long as special precautions are used to ensure that the temperature stays within the range for optimum application. Different chemicals can be added into the epoxy to allow for extremes in weather, such as hot or cold. Additives can also allow the epoxy to repair foundations cracks in dams and canals. In these specific cases, epoxy injection is the only type of feasible repair in order to prevent disastrous results if the foundation should fail.