Foundation wall

[MuirView Design]

We demo'd a wet laid brick stoop today in an area where the client has complained about water in the basement. We are removing the existing stoop and laying a paver pad. I can see the foundation is blocked up and has never been waterproofed. The foundation wall is looking very suspect to me. He is also getting ready to have the basement remodeled in the next few weeks and wants to address any water issues beforehand.

I'm wondering if I should recommend that we excavate that area out and address the block wall before we construct something on top. What should I recommend he do to waterproof....parge coat, foundation tar?

(Sorry forgot my camera today)

[Mbella]

Adam, I would first tell him to contact a basement waterproofing company and have them evaluate the situation before he finishes the basement. However, given the fact that you are there and ready to go, I would offer to do something in the area that you are going to close off.

If the house has a foundation drain, you could install a drainage membrane that collects the moisture (preventing it from touching the wall) and drains it to the foundation drain. If no foundation drain exists, you could apply a waterproofing (tar) membrane to the wall and install insulation board.

Although that's probably what the pros would do, I wouldn't warrantee it.

[MuirView Design]

So Mike, would you recommend excavating down the full length of the basement wall and taring the CMU and using the pink insulation board on the outside of that? Then bring it up with all cleanstone? Should I consider some type of drainage? I'll get out there today and take some pics.

How does a foundation drain and drainage membrane work?

[Mbella]

So Mike, would you recommend excavating down the full length of the basement wall and taring the CMU and using the pink insulation board on the outside of that? Then bring it up with all cleanstone? Should I consider some type of drainage? I'll get out there today and take some pics.

How does a foundation drain and drainage membrane work?

Since you are building on top of the area, that's probably what I would do. I would definitely use the clean stone. As you know, it's easier to install and will place less pressure on the block foundation wall.

The drainage membrane channels the water to the clean stone that is installed around the perforated foundation drain. The perf. pipe picks up the water and carries it to wherever it drains.....usually the sump pit.

[MuirView Design]

Is the drainage membrane a vertical sheet that gets placed against the wall? Don't believe I've ever seen one.

[Mbella]

Is the drainage membrane a vertical sheet that gets placed against the wall? Don't believe I've ever seen one.

I've never installed it Adam, but I used to do some digging for a basement waterproofing company that used it. The product in this link isn't what they used, but it's the same idea....http://www.superseal.ca/dimpledmembrane.html

I would go with the tar and insulation board.

[MuirView Design]

That's what I was picturing. Thanks for the advice.

[mrusk]

Adam are the downspouts piped away from the foundation? How is the grading in front of the house. I would try to get the water away from the house before I tried to keep it from entering the basement. Once you try to waterproof the basement if anything goes wrong its on your back.

[MuirView Design]

Thanks Matt. The downspouts are buried and have good pitch to daylight. I dug them up to make sure they weren't broken. It's only a 3" pipe though. I'm going to be running new sch 40 4" under the walk and putting good pitch on the patio.

Since none of the rest of the foundation is waterproofed, I am going to contractually absolve myself from liability. I just talked to the homeowner and he gave the go ahead to get it fixed.

Any advice on whether or not to do a parge coat before tar as some of the joints look a little decrepit? If I don't have to, I'd rather not, as it will set me back some time to let the mortar set up.

[Mbella]

Adam, I'm sure it wouldn't hurt, but I don't think I'd bother with the parge. I would plan on pressure washing the block though.

[custom patios]

parging is not waterproofing. it dampproofs.

[musclecarboy]

Adam, I'm sure it wouldn't hurt, but I don't think I'd bother with the parge. I would plan on pressure washing the block though.

Personally, I wouldnt bother. Let the tar patch up hairline cracks because its flexible and will penetrate and fill any areas where water could get in.

[Mbella]

Personally, I wouldnt bother. Let the tar patch up hairline cracks because its flexible and will penetrate and fill any areas where water could get in.


That's what I was thinking on skipping the parge. Definitely, want to make sure the block is clean though.

[MuirView Design]

The idea behind the parge coat was also a clean surface for the tar to adhere to. Pressure washing the block is going to be very messy. I'd almost rather hand scrub it with a bucket of water, apply a thin coat of mortar and adhere the waterproofer to that. Do you think it's worth it?

Either way, I have to definitely get some poly up and blast some heat to get the tar and block warmed up enough.

[Meanix]

parging is not waterproofing. it dampproofs.

Steve,
parging is barely dampproofing. I would consider the tar dampproofing. It is a back up to moisture that gets to the foundation wall, which has proper grading.

[MuirView Design]

Well the verdict on this mess was pretty simple. I was mistaken and the basement is not under the area we are working, but over to the left of the area. Once we dug it out the block didn't go down but two courses. The homeowner said his father in law laid the block. Someone needs to revoke his masonry license.

Anyway, we just cleaned the block and plugged all the holes with hydraulic cement, then applied a coat of Dry-Lok. It was a quick and easy fix. I still may use a piece of insulation board for vibrational protection.

[Mbella]

Good news Adam. I would definitely use the insullation board for protection.