Many foundation repair companies claim their epoxy injection will restore the strength of the wall without ever telling you the fine print that the epoxy manufacturers put on their product. Here are two examples:
Use epoxy to repair only dormant cracks. Repairing an active crack with epoxy typically results in a new crack forming near the original, epoxied crack.
For foundations where active movement continues to be a reoccurring issue, additional reinforcement may be necessary to prevent the development of additional cracks. For such scenarios, the added use of our [Carbon Fiber Power Grids] may be used in conjunction with the crack injection process.
If the crack was formed by tension due to differential settlement or bending due to wall shoving, then the crack will reappear. Their sales pitch may say the epoxy has 7000 psi tensile strength, but the interface between the concrete and the epoxy is the weak link. The concrete can only resist about 300 psi, which means if the forces that created the original crack haven’t been mitigated the crack is NOT dormant but still ACTIVE.
Client sent me this photo yesterday showing the crack reappeared. (Sorry for the small scale)
It does help if you read all the instructions and warnings on a product. As far as contractors go, there are a lot of crooks out there. It is necessary to read your contract carefully and protect yourself. “Never buy the other guy’s deal.” Uncle Frank
Morning, Randy.
As always, hope this post finds you well.
Great post. Thanks.
I have known the limitations to epoxy injection for poured concrete crack repairs for some time. The manufacturers claim, “will restore the strength of the wall” has limitations.
A: Installation process. B: Systems location to injection is essential.
A: Knowing how to do the repair with the equipment required. At times epoxy injection resins require to be under measured PSI. As well you have to know when to stop injecting epoxy resins. Moreover, the proximity to perimeter drainage weep tile arrangements.
The later can lead to reoccurring leaks and even weep tile blockage allowing soil water to navigate to others areas, in close proximity, further saturating soil in, around, and even under the footing causing unnecessary adverse affects to the foundation leading to more specialized work at greater cost expenses.
Understanding the difference between ‘active’ and ‘dormant’ poured concrete cracks is essential. Thank you for pointing that out. Great simple narrative to remember.
In Montreal Quebec, there use to be reams of poured concrete foundation epoxy injection contractors. Now there are a limited number, a hand full, of foundation repair contractors that utilize epoxy injection on residential poured concrete foundation cracks. Urethane injection is the baseline for poured concrete foundation cracks.
As for home inspection reporting poured concrete crack repairs. I use the narrative, “recommend a licensed poured concrete installation and service repair contractor.” When the foundation appears to have ongoing foundation cracks and related concerns, I add the word ‘specialist’ where contractor is used. "a licensed poured concrete installation and service repair specialist. Moreover, when all load bearing components, foundation, columns or pilasters have gone pear-shaped I add, “with a inhouse structural engineer.”
