Bricks, Masonry, Asphalt and Concrete - crack in foundation wall

hi

don't know if this is the right forum, but thought i'd give it a try

i noticed a crack in my foundation wall, don't know if it was caused by a basement waterproofing crew that i had in today that was doing some jackhammering, or if it's always been there.

anyways, the crack is visible on the inside and outside. viewing from the inside, it's about 3 feet long, mostly vertical, but slightly diagonal, not very wide at all (probably too thin to even slip a dime into).

having no experience with this, would people suggest calling in a contractor? wait and see if it widens or moves? just patch it up and forget about it?

thanks in advance

Does the crack start at the top or bottom of the wall?

If you can see it from the outside, I assume it is at the top, but wanted to make sure before trying to figure out the importance.

Dick

hmmm...i think it starts at the bottom, since it goes all the way down to the floor.

is there another way to tell? it doesn't really taper in width along the length

I assume you were having interior drain tile installed. They work well when installed properly (rock fill, etc.)

When waterproofers install interior drains, they usually remove a section of the floor about 12-18" wide that is about a foot inside the wall and is parallel to the wall. If a long section is removed, the lateral support for the wall is reduced and the wall could move and crack. Usually short segments (about 12" long) are left for support.

I do not know if this is what happened. Talk to your contractor with the jackhammer and explain the crack and ask if he could have done it.

It is not extremely serious IF you get the concrete floor replaced quickly. Because you have drain tile and and an opening, the water pressure cannot build up very high. The crack should be repaired (hydraulic cement) if it is below grade or water could come in before it has a change to get into the drain tile.

Dick