With all this wacky weather we've had this year in Massachusetts, Connecticut and Rhode Island, the soil has done a lot of freezing and thawing that doesn't bode too well for concrete. But it doesn't just affect concrete, but block and stone walls as well.
You have to remember that most soils retains water to begin with, they're moist. But then we have the rain, snow, melt, and freeze. Then the rain, snow, melt and freeze again. We all know water freezes, and when it freezes it expands.
Well, concrete and block are very strong when you push down on them. But, when you push in on them, they're not quite as strong. In residential construction there is no requirement to put re-bar in it. So, when you have this freeze thaw cycle happening and it pushes against the foundation you are going to get cracks.
These foundation cracks are caused by the freeze thaw, but it is also caused by the pipes running through the foundation walls. If the pipes are not located below the 4' freeze line, and we have a deeper freeze than that, those pipes are going to push up on the concrete. This can cause cracks too.
We see a lot of do-it-yourself situations where people try to fix foundation cracks with Flex Seal that they see on TV or with hydraulic cement. With the weather, concrete expands and contracts itself and hydraulic cement does not. So we get calls from homeowners who have tried to fix the cracks but it just doesn't work.
This cycle is a natural thing that happens, but there are some preventative steps you can take. Make sure the gutters are clean and the downspouts run away from the house. Make sure the landscaping is pitched away from the house. If you have a crack, the water gets in there and freezes and expands the crack, or the soil pushes against the crack and expands it and you are going to have water come in.
What we do is we either inject the with a closed polymer resin by drilling at angles to the crack every six to eight inches, putting ports in, and then injecting the resin. Or we may look at it and use another method where we put another material into the crack and then a weave carbon fiber blanket on top of that. Then the customer gets a transferable warranty on that.