What do I use to fill the holes in the foundation blocks?

Answer by  Christian9247 (5042)

The best thing to use would be concrete. Concrete fills in the holds of foundations also adding a secure foundation in the process. Other materials such as spackle and tar will either not add the support needed or they will corrode and dissolve over time. Some would even say use water proof coating once you've filled the hole.

Answer by  Esme (535)

If the hole is small, concrete caulk can be poured to fix it else patching materials are used and sealant is applied as final coating to fix huge holes.

Answer by  philg1961 (347)

Your question is ambigous. If you are filling the block cores, use a standard concrete mix. If you are filling small holes between the blocks, use mortar mix.

Answer by  kory88 (109)

To fill the holes in the foundation blocks you would put concrete into the holes to fill them and make it seal.

Answer by  canenguez (123)

You use pllywood inside the hole and outside the hole, leaving enough room at the top to pour the concrete, another way using cement/concrete tubes, using a caulking gun.

Answer by  worker9228 (87)

I would use a waterproof concrete to fill in the holes. First start mixing the concrete perferably hydro plug to stop any leaking involved. then patch the remaing holes and fill in any other voids in the foundation block. We must try to keep the concrete mixed a a good consistency to work well.