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Water Seeping Through Cinderblock Walls

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R James

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Over the last year or so, water has begun seeping through the cinderblock walls in one section of my basement.
At first this was only during a particularly heavy downpour of rain. Now even prolonged, steady rain will cause this to happen.
At its worst, the water actually squirts out of the bottom blocks in two locations, but "weeps" out along the walls in the section starting about 5 feet from the ground.

When this happens, you can actually hear the water running inside the cinderblock wall.

I've spoken to several folks about this and am eyeing a number of solutions. I attempted one and the results are puzzling me, hence this question.

Since I already have an interior french drain installed, I drilled about a dozen weep holes along the bottom row of cinderblock.
My thinking was to relieve the hydrostatic pressure building up within the walls and to give the water a means of egress.
(At least for the time being - this Spring I would very much like to work on keeping the water outside the home altogether by resealing the cinderblock from the outside. But I digress.)

Over the last 24 hours there has been a lot of rain.
I expected to see the water running out of the weep holes I just drilled.
Although some water is dripping out of them, the entire wall, starting about 5 feet from the ground, is still streaked with "weeping" water.
I am at a loss.

If I understand correctly, there should be no more hydrostatic pressure. The water should take the path of least resistance, and flow to the bottom of the blocks.
As the blocks start to fill with water, the water should pour out of the weep holes.
There should not be five feet of water in the blocks! Why are they leaking so high up?

(to be clear - they blocks aren't leaking where they reach the ceiling - rather, they're leaking/weeping about 2/3 up from the ground (5 feet)).

Any and all thoughts and suggestions would be most welcome! Thank you.
 

Snoonyb

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Welcome.

Water will follow, and find, the path of least resistance, and if you're waterproofing membrane has failed at the 5' level, that would be far less then percolating to the greater depth.
 

Jeff Handy

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You don’t say where you are from.

I had a concrete block basement with the exact same issue.
Blocks always weeped, and some had little streams during big rains

I never was able to fix it, but I was advised that the solution would be to excavate all around, seal the walls, install a drainage membrane backed up with gravel, backed up by landscape fabric to keep the gravel clean.

So I just lived with it.

One company I had found online offers a system similar to what you started to do.

They sell a kit that is basically a hollow plastic baseboard system.

You drill a hole right at the bottom of the wall, into the hollow block, about every foot, and blow it out to ensure water can get through.
Then the baseboard is glued to the floor, and it conveys the water to a sump basin.

There are coating systems to waterproof concrete block walls, but they have to go on clean intact surfaces, no paint or loose mortar.
I think one is called Dry Lock.

You could contact some basement waterproofing companies locally for advice and bids.
 

R James

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Thank you so much for those replies!
I'm from NJ (USA).

As for the first response, here's what I don't get:

The blocks are hollow.
So if the exterior waterproofing is compromised 5 feet down, the water would seep into the cinderblock.
But wouldn't it flow DOWN, through the hollows, to the bottom level/bottom row of cinderblock?
It seems to be defying gravity (and other laws of nature) to bypass the hollow centers of the cinderblock and come out on the other side (the side facing the interior of my basement).
 

Jeff Handy

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Water is being drawn or pushed through voids or cracks in the mortar between blocks.

By capillary action or just by surface tension.

So water IS falling through to the bottom, and is being handled by your foundation drain, but some is also being pulled or pushed through the wall through defects that run all the way through it.
It is crossing the edges and middle of some blocks like a bridge.

Your wall might also be bowing in, which would make it even more leaky at the joints.
 

R James

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Ahhh - I see.

So, on the bright side, there should certainly not be five-feet of water filling the hollows of my cinderblock. (It happens - I've seen it on the Internet so it must be true.)
And there should be no hydrostatic pressure on my walls or foundation.

But on the negative side, the water is still running around inside my walls doing whatever it feels like doing -- dropping off effervescence along the way, perhaps promoting mold growth, etc.

In other words, I still have reason to hope that my efforts have resulted in some modest improvement to the situation. The real test will be when there's a truly heavy downpour - the kind that caused the wall to literally squirt water from the bottom layer of cinderblock.

Assuming I no longer see that, I'm faced with the same predicament as you, Jeff: do I just live with this or tear out the earth abutting the leaking wall to re-install a water barrier, etc.

Thanks again.

PS: Since you live with it, is there anything you do to inhibit mold growth?
 

Jeff Handy

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First of all, you can still have hydrostatic pressure on the wall, even with plenty of water leaking or weeping through.
Not all the water is getting through or running to the footing.
You can also have high soil pressure against it, soil expands with rain, especially clay.

I don’t live in that house anymore.
I just stored everything up off the floor, on shelves or skids.
Occasionally hosed off the walls and floor into the sump pit, after setting up towels to catch any crud that might kill the pump.

I bleached everything once, after a flood due to long power failure.

Basement was unfinished, just storage and work space.
 

Bob Reynolds

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I would go with the basement exterior wall membrane has failed at the 5 foot height. Keep in mind that water is always going to flow down the exterior of basement wall. You just have to properly deal with the water and channel it beyond the structure. If you don't do this, then the water will enter the structure as you are finding out now.

The only real way to fix this is to excavate the soil from the exterior walls down to about 18-24 inches below the footing. That sub footing area is then fitted with a drain pipe and gravel (also known as a french drain) to channel the water away from the structure. The exterior wall must then be sealed with a good quality membrane (like dry pro) so that the water will run down the outside of the membrane and into the gravel and drain pipe. Then back fill the dirt against the wall and replace the ground cover, shrubs, bushes, etc. taking care to slope the back fill away from the structure. This will prevent the water from seeping into the wall (because of the sealed membrane) and the water that does flow down the outside of the wall will channel into the french drain and flow away from the property.

This sounds more complicated than it really is. It's a messy job, but it can be completed in a few days. You will want to find a company that specializes in this type of work. Get three estimates and then make your decision. The prices do vary depending on the efficiency of the company. Companies that are "geared up" to do this work are gong to be your best bet. They are also normally the least expensive. As always get references from past customers with the same type of issue.
 

EricK

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Have you considered a french drain around the perimeter of your house? I don't mean the type that was originally put around the base of the wall. This would be one that is about 4 ft away from the house and about 2 ft down and 6 in wide. Basically, you make a trench around the house that would lead or redirect water away from the house to a different location. This may be a very good solution for you depending on a few things of course. Without going into too much detail, check this article by Ask the Builder, Linear French Drain Systems
 

Steve123

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So if the exterior waterproofing is compromised 5 feet down, the water would seep into the cinderblock.
Actually, it is unlikely you have waterproofing. You have "damp-proofing". Just a layer of tar-like material to keep the blocks from staying wet (concrete is in fact somewhat water permeable). How old is the house ?

As mentioned, water will find the path of least resistance. If it has found a path from a failed mortar joint 5 feet up, across a solid portion of the block, and down your wall, thats where its going to go. But if you french drain is collecting that water, its doing its job. You could try re-pointing the interior joint at that location, but you risk chasing your tail trying to find every bad interior joint.
 

mabloodhound

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Although your blocks may be hollow, they may also have been filled with mortar, either partial or fully, and thereby preventing a good drain down to your drilled holes.
 

R James

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Again thank you to everyone for these replies.

there’s about three feet of crushed stone around the perimeter of the house (built in 2001) and a lawn thereafter.

the crush stone and the soil directly underneath it - in the affected area, right next to the outer wall - stays remarkable dry actually. No puddling.
The lawn area about four feet out is a little concave and does get very very swampy. Puddles and everything.
I pointed this out to a contractor and he dismissed the notion that the standing water on the lawn could be feeding the water that’s coming through my wall four feet away.
That doesn’t seem right to me.
To me (as per the article shared above) the water spreads out underground in all directions. When if gets too saturated it reaches the compromised wall and finds a way in.
That’s why I love the idea of a drain about four feet out and two feet down. Couple that with some better grading of the lawn and I think I can keep a lot of water away.
this would be on top of waterproofing the exterior of the affected area.
 

sadavis80

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I'm certainly FAR from an expert, but still surprised that no one has mentioned this...
Have you looked at the SOURCE of the water at your foundation? One item that pops up to me is GUTTER water. If you have gutters, where are the downspouts dumping? Can you route them further away from the house? I solved a similar problem in my previous house, but moving one downspout and adding extension hoses to the bottom of others to route the water out about 8 feet from the foundation. If it takes care of the problem, it beats the crap out of digging up your foundation dirt ;). If you don't have gutters.. then GET SOME - still WAY less expensive and labor intensive than digging dirt down to the bottom of the wall.
Steve (amateur speculator)
 

R James

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Thanks.
yes I have gutters and buried downspouts.
(in fact in connection with this issue I just buried the only one that wasn’t buried)
When we start digging one of the things on our list to to trace the downspouts and make sure they’re intact and see where they’re going
 

Jeff Handy

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Also get rid of the crushed stone around the house.
Instead of being a raised slope of soil that sheds water away like a ramp, the crushed stone acts like a trench, any rain or runoff that gets into it can only go down into the ground to drain.
It should be dug out and replaced with soil, or solid paving, or patio blocks, higher than the lawn.
 

R James

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As a head's up to anyone who might come across this thread someday:

One thing that drilling the holes along the cinderblock wall seems to have done is to raise the radon levels in my basement dramatically.

I have a radon abatement system and a monitoring device.
Before the holes were drilled, my basement radon level averaged around .75 (pci/l).
Three days after the holes were drilled, they rose to 3.75.

Now, the weather pattern changed here as well - it did get significantly colder. And that can affect radon levels. I only purchased the monitoring device this past summer, so I haven't used it through a late fall / winter season yet. I have no comparable data. Nevertheless, the numbers rose fairly dramatically.

Two days ago a purchased rubber beaker (lab) corks to plug the holes I drilled.
The numbers have come back down.
Yesterday, levels were around 1.1.
Today, levels went as low as .75 again.
 

tomtheelder2020

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Jeff is right about pressure on the wall. If the full height of soil against the wall is saturated, pressure on the wall is effectively the same whether or not water is coming through the wall at any level.

Bob R recommended excavating to 18-24 inches below the foundation. That is a very dangerous thing to do, possibly resulting in bearing failure of soil beneath the footing and structural damage above. Consult a soils or foundation engineer before digging (experienced contractor will have one they work with regularly).

Preventing water from reaching the foundation is much better than collecting it at the foundation. EricK’s suggestion is a good one, and re-grading as you suggest are right on the money. Jeff H is right that water can be infiltrating soil under the crushed stone even if not apparent but permanently removing the stone isn’t necessary. For a similar situation at my house I laid plastic sheeting on the soil (graded to drain away from the house), then filter fabric to protect the plastic, and covered that with the stone.

[TS1]
 

R James

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Thank you Tom. Unless something changes, that's my plan. Will have to wait until the Spring though.
 

BuzzLOL

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I've never seen a newly built home that the basement didn't leak! That is, BEFORE the ground level outside was filled in, finished smooth, and properly sloped away from the house and gutters installed that drain AWAY from the house above ground! Then, almost magically, the basement stays dry...
Around here in N.W. Ohio there are also new houses with WOODEN wall basements! They use a foot of gravel around the basement walls that allows any water that comes near the home to fall down below the concrete floor level and go into drains. Which sounds similar to what you have.
The upper ground layer near the house should slope at least 5 - 10 feet away from the house and the entire yard should have a slight slope to allow water to run away somewhere safe such as a street with drains in front, pond/lake in the rear, side yards should peak and flow front, rear, or both or flow far away if no other houses nearby. Downspouts shouldn't be 'buried' unless flowing to some kind of fresh water sewer system... maybe to the street out front... Downspouts should go at least 5 - 10 feet away from the house. We hinge our downspouts on the bottom so they can be swung up for mowing the lawn or to protect them from foot traffic in dry weather.
BTW, are you basement walls black "cinder" blocks or white 'concrete' blocks? Cinder is a hard black substance left over from burning coal. It's also drier than concrete.
 
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