Water coming through cinder block foundation
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Water coming through cinder block foundation
The bulk of our house is built on a poured foundation and that's fine. There's no water getting through it during rain. However, under the laundry room, it switches to a crawlspace and uses a cinder block foundation. Between the two foundations is a gap and water has flown in an eroded most of the dirt fill supporting the foundations. We happened to have a heavy rain a few days ago and I opened up the crawl space and I noticed there was water coming through the cinder blocks and pooling in the crawl space/
Is this something I need to be concerned with? I plan on adding more back fill to replace the missing dirt. I should also add that the joints on the cinder blocks need to be repointed but I'll get to that some day.
Is this something I need to be concerned with? I plan on adding more back fill to replace the missing dirt. I should also add that the joints on the cinder blocks need to be repointed but I'll get to that some day.
#2
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You need to regrade on the outside to move the water away from the wall in the first place. Yes, this is something about which you should be VERY concerned.
#9
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How far below grade is the gap? I would dig/excavate on the outside so you can fill the crack from both sides using type S mortar. Then I would apply a damp proof coating (tar) to the exterior before back filling.
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The gap goes from the top of the foundation and most likely goes all the way to the bottom of the foundation. Would I also need to apply the damp proof coating to the cinder blocks that are on the garage? I'll post some photo's later.
https://www.lowes.com/pd/UGL-White-W...-fl-oz/3073099 I found this. Would this work?
https://www.lowes.com/pd/UGL-White-W...-fl-oz/3073099 I found this. Would this work?
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I talked to my dad about what we need to do and he figured that we'd have to do this. This is my basic plan. Is there any other steps that I should do?
Also, what tool do you all recommend to apply the mortar? There's a tool for repointing but I don't remember the name.
- Excavate the foundation
- Remove loose mortar and clean the the area of dirt and debris
- Fill the gap with mortar and repoint any loose joints on the cinder blocks
- Let the mortar dry and apply one or two coats of damp proofness
- Backfill
- Done!
Also, what tool do you all recommend to apply the mortar? There's a tool for repointing but I don't remember the name.

#18
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You can use a grout bag to squirt mortar into the crack but I generally use a trowel. Or if you wear gloves you can use your hands to pack it in.
I would use a wire brush to clean the foundation on either side of the crack to get it good and clean before applying a damp proofing. How far you go away from the crack depends on your energy level but I'd go 6-12".
I would use a wire brush to clean the foundation on either side of the crack to get it good and clean before applying a damp proofing. How far you go away from the crack depends on your energy level but I'd go 6-12".