Concrete foundations do crack, and it isn't always a major concern. In the process of removing their flooring material, many people find cracks in the foundation that are worrying. Obviously, some cracks can be problematic and even cause structural issues, and these cracks can affect the stability of your floor and lead to moisture seeping up from the soil below it. Basically, if you remove your flooring material and your concrete foundation has some cracks in it, you want to have it inspected by a professional.
A professional foundation repair contractor will be able to tell you how severe the cracks are and what you should do about them. Usually they will tell you to leave the small cracks alone because they aren't going to damage anything. They might also offer to seal the cracks using a variety of different finishes. But most of these small repairs can be done yourself if you want to save some money. There are a few different products you can use to fill concrete foundation holes and cracks.
Silicone Caulk for Thin Cracks
For most narrow cracks, you want to use a silicone caulk. There are many caulk products designed specifically for concrete that can easily fill in small cracks. Using silicone caulk is essentially just like gluing your cracks. The caulk isn't going to hold your concrete together or even necessarily prevent the cracks from becoming larger. But it does seal the crack so that dirt and moisture can't get inside. Even though it can kind of look sloppy, it is a very useful solution for narrow cracks.
Concrete Patch for Holes and Chips
If you have actual holes and chips in your concrete that are only on the top surface, you probably want to use something different then a silicone caulk. If your hole doesn't go all the way through the foundation, you can fill it in with an actual concrete patching solution. This is a putty-like substance that is granular and much more similar to actual concrete. Basically, it is a mixture of concrete and glue that, when it dries, looks very much like normal concrete. Concrete patch doesn't come in caulk form. Instead it comes in tubs so you can apply it to the surface with a putty knife.
Most likely, you will need to use both patching solutions in order to repair all the minor damage to your foundation.
