Problem basement floor - suggestions welcome

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SidecarBob

Retired & too busy to go back to work
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Sep 24, 2017
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Location
Kawartha Lakes, Ontario
My Mum in law's basement flooded; The tile and foundation have been dealt with and it has been dry for a few months and, since I know how to do stuff and my brothers in law both have to work for a living I was "elected" to restore her rec room.

Most of the damage was to one outside wall. We stripped it to the foundation and I've re-strapped, installed rock wool, vapour barrier and drywall and I'll be taping this week (I've also repaired the adjoining walls).

The walls are a pretty straightforward job but I have no idea what to do with the floor. It is a typical late '40s or early '50s suburban cookie cutter house with concrete block foundation and poured concrete floor. It was my father in law's parents' home but I don't know much about its early history. My inlaws inherited it in the '70s, had a small extension added before they moved in and finished the basement right away.

There was Ozite carpet on the floor with a layer of plastic vapour barrier sheet underneath and most of the concrete is covered with a black, tarry substance. Mum in law says they noticed that the floor was damp after they finished the basement so they had someone dig up around the edges of the floor and install a weeping tile. Brother in law tells me that he always remembers carpet in the rec room and that even after the weeping tile was installed the carpet became damp so they added the plastic. Neither one remembers who added the tarry stuff or when.

As you can see from the pic, there isn't a lot of room to work in there so I will have to finish the half of the room nearest to the wall I'm repairing before we can move the stuff that is piled up in the other half and work on that (there's nothing I can do about it - she's in her '80s and won't be convinced otherwise).
floor.JPG

I would really prefer not to put carpet back in there again if I have any other choice but the tarry stuff is uneven so it pretty much eliminates tile, rolled flooring or one of the paint on floor finishes. A raised floor would be ideal but the ceiling is only 78" now and we don't want to reduce that.

Anyone have an idea of what I can do with this mess short of grinding the floor (not really an option either)?
 
The black stuff is the glue that was used why back when, if you have solved the problem with water I would replace what was there.
If you are worried about moisture, the test is to tape down squares of sheet poly and see if you trap some moisture.
 
The carpet wasn't glued down. The black stuff is under the plastic sheet so I think was something they put on the concrete to seal it. Unfortunately, my father in law and his friend that helped him are no longer around for me to ask about it.

The source of the flood has been fixed. But shortly after the weeping tile was installed they put the plastic under the carpet so the carpet would stay dry so I am not convinced that the moisture has been completely eliminated.

Then again, the carpet stayed dry for about 40 years...

On the other hand, carpet collects dust and I don't see a woman in her 80s vacuuming the basement very often...
 
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Old lino tile had asbestos and so did the black glue and that is what it looks like when it has been scraped up but the last layer was not dissolved and removed. You can still check it for moisture coming up.


If you use this test and get any water then you go onto having further testing done. Keep in mind there is nothing you can put on top of the floor that will stop moisture, Carpet is often used because the moisture will wick thru it and evaporate. The smell is often just a matter of not enough air circulation in the room.
 
The "black glue", may or may not be "cutback adhesive" which was associated with flooring products that used asbestos as a binder and there is a simple test;If a few drops of boiling water applied simply set on the adhesive, with no affect, the adhesive is cutback. If the adhesive melts it is not cutback and contains no asbestos.

And to think, I spent years with a blow torch and a scraper removing cutback adhesive, with no protective gear, and no ill effects.
 
Because of the effects of loose asbestos fibres people have become terrified of asbestos in any form. I seriously doubt that rubber/asbestos tiles ever did anyone harm outside of the factories where they were made. Heck, when I was in grade school we did art projects with asbestos clay and being kids we even tasted it but I've never heard of anyone being harmed by it. I do wonder how much of the asbestos powder the teachers inhaled when mixing the stuff, though...

I am convinced that the black stuff is not a tile adhesive. As I said before, the original concrete floor was dug up around the edge when they installed the weeping tile (apparently the house now has weeping tiles both around the outside of the foundation and around the inside below the floor) and it has always had carpet since then and the black stuff seems heaviest over the areas where the floor was dug up.

I think it may be some sort of bituminous damp proofing or something similar. I wouldn't put it past the father in law's friend to have recommended they coat the floor with driveway sealer.

Whatever the black stuff is I do NOT want to remove it unless it is absolutely necessary. Mum in law's place is almost 2 hours away from ours so I can only be there for one overnight per week and when I go I have to spend the night in a sleeping bag on the living room floor which is hard on my arthritis so I want to get it done as quickly as I can. It has already become a bigger job than I agreed to and my own basement reno has slowed to a crawl because I spend half a day getting ready to go there, 2 days going, working & returning and another recovering from sleeping on the floor every week. And I am less concerned with the new flooring stopping moisture than I am with having something that looks presentable and is easy for her to maintain.

BTW: I am confused. Do you want me to tape down squares of plastic to test for moisture or, as that video recommends, buy an expensive testing system that I am not likely to ever use again?

Also, I'm no expert so I may be wrong about this but wouldn't the water table will be lower this time of the year so if moisture is going to come through the floor it will be more likely to happen in the spring when the ground thaws and it rains instead of snowing?
Although the thaw & melt this past week may have simulated that somewhat - we are leaving for there shortly so I'll have to see if I can lift back some of the remaining carpet and look for moisture under the plastic when we get there.
 
You could lay down a floor leveling compound then your choice of vinyl or wood/fake wood flooring.
 
BTW: I am confused. Do you want me to tape down squares of plastic to test for moisture or, as that video recommends, buy an expensive testing system that I am not likely to ever use again?

Also, I'm no expert so I may be wrong about this but wouldn't the water table will be lower this time of the year so if moisture is going to come through the floor it will be more likely to happen in the spring when the ground thaws and it rains instead of snowing?
Although the thaw & melt this past week may have simulated that somewhat - we are leaving for there shortly so I'll have to see if I can lift back some of the remaining carpet and look for moisture under the plastic when we get there.
With the drain inside you should have no problems but block walls can be trouble and should have been draped so any leaks would have been sent to the drain below the floor. But you haven't made it sound like you have that problem.
The plastic taped to the floor should prove you have no problem. If they did a driveway sealer on the floor the smell off that would be horrendous for a few years.
 
I'm there now and I just lifted back some of the carpet and plastic and it doesn't seem wet. I have some small pieces I cut out for the window when I did the vapour barrier so I'll put a couple of pieces of it down over the barest parts of the concrete when I'm done for the day and see what it looks like in the morning.

I thought about a levelling compound but I don't know what will work. The black stuff is about 1/8" thick but it is fairly soft so I think a more solid in the gaps might not be great.
 
I've been thinking about this while I taped the drywall. I wonder if 12mm laminate flooring like this would be OK, laid as a floating floor right over the stuff that's there?
https://www.rona.ca/en/laminate-flooring-hdf-12-mm-beige-grey-84665701

BTW: I have put a couple of pieces of clear sheet on the floor overnight and I'll see if there's any condensation under them in the morning.
 
Hmm... Vinyl would nearly double the cost. Did I mention she is a senior with fixed income?

Besides, isn't the vinyl more flexible than the laminated stuff? And wouldn't that let the uneven substrate telegraph through?
 
Hmm... Vinyl would nearly double the cost. Did I mention she is a senior with fixed income?

Besides, isn't the vinyl more flexible than the laminated stuff? And wouldn't that let the uneven substrate telegraph through?
They all want a level or flat floor , I am in a dry basement with some of that cheaper laminate in one room that stayed dry when I had little flood the rest was replaced with tile.
It is fine but where the floor is uneven you do feel it like a little spongy.
 
I spoke to Mum in law about the flooring, half expecting she would insist on replacing the carpet with more of the same but she said she hates carpet and would rather have something she can sweep with a broom. She is very receptive to the idea of some sort of plank, either laminated or vinyl and is willing to spend the extra for vinyl if it is better (I told her it might hold up better if she has another flood) but not for an underlayment unless absolutely required.

Now I need to find out if I can I lay vinyl over the uneven substrate (failing that we'll get the thickest laminated stuff we can find.
BTW: I got the drywall taped and the first skim coat on this week. Next week will be 2 more skim coats (I'm not good enough to do it in 2) and (hopefully) the week after that sanding & paint so if all goes well we'll be buying the flooring in 3 weeks and I want to have all the decisions except colour made before then.
 
In the pic above the dark areas are the black stuff and the light areas are bare concrete. The black stuff is approx. 3mm thick and fairly soft but not exactly what I'd call gooey. The old carpet & plastic sheet was down for about 40 years and I suspect that moisture coming trough the concrete during the last few years and being trapped under the plastic sheet caused the black stuff to let go of the concrete in areas (some waterproofing, eh?) so that after we removed the carpet and plastic and allowed the floor to dry we could sweep up the loose stuff (the other side of the room is going to be the same from what I can tell).

A bit more history (this may also help someone else avoid a similar problem): Whey my in laws first moved there both of their then teen boys' bedrooms were in the basement (rec room on one side, bedrooms on the other) and after both of them grew up and moved out our son lived in in one of those bedrooms for a few years while he was in college. After he moved out my father in law was the only one that spent any time in the rec room but even that tapered off as the illness that did him in 7 years ago progressed.

During all the time the room was regularly used a wet carpet would have been noticed but since then the only time anyone went in there was Mum in law accessing stuff she has stored in the bedrooms and the brothers in law occasionally going through it to the "workshop" (barely big enough to swing a hammer so really more of a tool room) when they did the occasional repair, which meant that nobody walked on the carpet without shoes.

We were visiting Mum in law one day last spring when on of our daughters called Kay (my wife) and she went downstairs so she could hear (Mum is half deaf so the TV is always loud) and happened to wander into the rec room in stocking feet. We have no idea how long the carpet was wet before that.

We moved the stuff on the wet side of the room onto the dry side and rolled up the carpet but we couldn't do much more right then and Mum wouldn't allow workers in without someone she trusted to keep an eye on them so it would have to wait until Kay retired a couple of weeks later. We were leaving her retirement party on her last day when she got a message that her Mum was in the hospital. For several months we weren't sure Mum would make it and weren't sure if she would be able to return home if she did so from spring until December Kay spent 2 or 3 weeks with Mum and 2 or 3 days at home During that time Kay arranged to have the weeping tile and foundation looked after and the brick chimney repaired & re-flashed (water damage to plaster wall & ceiling in kitchen that I may end up tackling after the rec room is done). Kay will continue to go there for one overnight per week (often timed so she can accompany Mum to a medical appointment) for the foreseeable future (while I am working on Mum's place I travel with her).

Mum is doing pretty well now but at 86 and with her health concerns it is understood that she won't be able to live on her own for many more years. Most houses that are sold in her area and up being bought by builders (that knock them down to build huge, ugly piles that barely fit on the lot) so there really isn't a lot of incentive to spend a lot of money on fixing the place up beyond what will keep it safe and make it more comfortable for her, which explains why I am trying very hard not to spend any more money on this job than necessary but at the same time make it look nice for her.
 
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