Plastic under floor chipboard

[Stew]

Hello,

I'm renovating the basement. I've torn everything down to the concrete, installed the leveling system, followed by floor chipboard and EPS foam with milled tracks for underfloor heating pipes. On top of this, I was considering a thinner layer of floor chipboard. Do I need age-resistant plastic between the foam and the chipboard?
I have bought plastic and it's not particularly hard to lay, so it doesn't matter to me. But the question is what is correct and proper?

Regards,

Stefan

 

[kimpo]

Unfortunately, the plastic should have been on the concrete floor before you laid the leveling floor. IF you are absolutely sure that you don't have incoming ground moisture, which is usually the case in basements. Since I suspect you don't want to redo everything now, skip the plastic altogether; otherwise, there's a risk that the first chipboard floor, i.e., the one against the leveling floor, will deteriorate.

A better alternative would have been if you had placed the foam directly on the concrete slab, plastic, and then chipboard. But you probably don't want to hear that now either...

Good luck!

 

[Stew]

Unfortunately, the plastic should have been on the concrete floor before you laid the leveling floor. IF you are absolutely sure that you do not have incoming ground moisture, which is usually the case in basements. Since I suspect you don't want to redo everything now, skip the plastic entirely; otherwise, there is a risk that the first floorboard, i.e., the one that is against the leveling floor, will become damaged.

A better option would have been if you had laid the foam board directly against the concrete slab, plastic, and then the floorboard. But you probably don't want to hear that now...

Good luck!

Hello,

I don't agree with that. Nivell says nothing about having plastic against the concrete floor; they do not recommend this. My thoughts on this are that instead of transporting away the moisture, which is done with a ventilated leveling floor, you instead trap the moisture under the plastic. If you place a piece of plastic on a concrete floor and let it sit there for a few days, it's definitely moist underneath.

Placing foam board directly against the concrete is an option, cheaper than leveling, but not better. Foam board is great for avoiding organic material against the concrete, but it's the same as placing plastic directly on the floor; the problem remains. If instead, as with the leveling floor, you transport away the moisture, you avoid it entirely. Both with foam board and plastic directly against the concrete, you trap the moisture.

That's what I think, anyway

 

[kimpo]

Nivell doesn't say anything about using plastic against the concrete floor; they do not recommend this.

That's absolutely right, but unfortunately, the flooring manufacturers say it should be plastic if there's a risk of moisture.

But as I wrote, go ahead, but skip the plastic. That way, you won't trap any particle boards under plastic.
Unfortunately, Nivell doesn't transport moisture away from the floor without a fan, but it helps to ventilate the space and ensures there is no organic material against the damp concrete floor.

Good luck with the floor!

 

[Stew]

Absolutely right, but unfortunately, the floor chipboard manufacturers say it should be plastic if there is a risk of moisture.

But as I wrote, go for it, but skip the plastic. At least then you won’t be trapping any chipboards under plastic.
Unfortunately, the Nivell floor doesn't remove the moisture without a fan, but it helps to ventilate the space and ensures that there is no organic material against the damp concrete floor.

Good luck with the floor!

Yes, you might be right. I'll skip the plastic entirely.

Now I have a ventilated floor, with dual channel fans blowing air in. I hope this can help keep the moisture at bay.