How do I waterproof my basement ceiling

[serenity]

So I can find heaps of info on waterproofing floors and walls, but what I need is to seal the polished timber floors above.

Every time one of my dogs pees inside or someone spills something on the floor it drips between the floorboards and into my basement. So far my oldest puppy has destroyed a rather expensive air hockey table.

I want to seal the floor above somehow so I can sheet the ceiling and add down lights and finish off my den.

Anyone know of any products that can be applied to an already polished timber floor?

 

[KLF]

I would work on the dog first.

 

[serenity]

I would work on the dog first.

Lol, almost had him trained, he would let us know he wanted to go outside. Then all of a sudden he decided he would just do his business wherever. I am no expert at dog training though. Love my dogs but I am in the deep end and learning a lot of things the hard way.

 

[swelltimes]

X2 on training the dog.

What about a marine-grade clear epoxy on the floor? Not sure how it'd look if there's a ton of shoe traffic on it, but it for sure won't let liquid through the floor. You may have issues with expansion / contraction of the floor if your house has big swings in humidity.

 

[rusty_tlc]

No subfloor under the hardwood?

 

[45Kevin]

So the pee is passing through gaps between the floor planks. I will assume that they are not tongue and groove.

So you need to fill the gaps. Use a paintable caulking that is close in colour to the wood. Wider gaps can be filled first with a styrofoam backer rod. Be neat with it and apply a new coating of finish over the floor.

If they are T&G, they must be very loose fitting and you could go to the trouble (if possible) of pulling them up and resetting them tighter. Or go the caulking route.

 

[serenity]

The floor is tongue and groove and has been sanded and polished very recently. Liquid passes straight through though, had a few spills in the kitchen as well which have ended up down there.
I will have to use something flexible as I live in an area with a massive variation in humidity so whatever I use will have to be able to cope with that. I was hoping there might be something i could spray on underneath to seal it.
The underside looks like this but without all the junk on a shelf.
Top looks good though.

 

[Redgrrr]

Had too sorry

 

[Redgrrr]

Add a humidifier in the basement and keep the floor at 8-12% I would think that would help swell the joints back up, is the floor a mix of soft and hardwood?

Do you have any carpenter buddies with a humidity tester? The ones without probes seem to be more accurate and read up to an inch deep.

 

[swelltimes]

I think you'd be in for bigger problems in the long run if you did something to capture the liquid below the floor and above the basement ceiling. Humidity's a huge factor, but if you can capture the liquid ABOVE the floor, that's ideal. Once it goes below the wood, yet not leaking into the basement, you're in for years of smelly, moldy trouble.

How about pulling the existing wood floor, laying a subfloor of OSB, and putting some linoleum or other relatively seemless material?

Seems like that may be way better in the long run.