Basement Remodeling Update and Installing Subfloor to Prevent Water Damage

Bob discusses the installation of a plastic subfloor to prevent water damage and the selection of a basement dehumidifier.

Clip Summary

Bob recaps the work done so far in the basement remodeling project. The Owens Corning Basement Finishing System has provided the walls and the ceiling for the new basement family room. One of the most important facets of this project is preventing moisture from causing damage in the basement. Bob talks with Larry Janesky of Basement Systems Inc., about the equipment being put in place to prevent moisture damage. An underlayment is being put on the floor to prevent water transfer. The underlayment is a plastic interlocking subfloor made specifically for basements. Organic material, like wood, should not come into contact with the concrete subfloor because water vapor rises up through the concrete and can create problems with mold. Traditionally, people remodel basements by putting visqueen down on the concrete, laying down pressure-treated 2x4's, insulating in between the boards, and then laying down a plywood subfloor. The ThermalDry inorganic underlayment is a better solution as it has tracks to allow some air circulation. With a traditional subfloor, water vapor condenses into water underneath the visqueen then transfers to the wood and organic materials in the subfloor, causing mold and rot. Plumbing leaks can also result in a wet subfloor, causing the plywood to buckle and mold to grow. ThermalDry underlayment is quick to install, which saves time and money. The panels lock together with teeth and a shiplap design to stop the water vapor. The tiles allow for a little expansion and contraction and take up only a half-inch of the basement's ceiling height. This underlayment system costs about the same amount as the traditional method but, unlike traditional subfloors, does not require replacement after a water episode. If there is a water problem, the tiles can be lifted up, dried, and put back in place once the water issue is addressed. On a flat floor, the tiles will lay flat and the perimeter tiles will be secured to the floor. The completed floor will be made up of three layers: the underlayment, the pad, and the carpet. These multiple layers will minimize any sound from the rigid plastic coming into contact with the concrete slab. The Melrose home has a wavy basement floor, so extra fasteners will be put in to hold the underlayment down. A dehumidification system will be put in the basement to draw water out of the air before it becomes a problem. It's important to use a dehumidifier designed specifically for basements as most dehumidifiers are rated for 80 degree temperatures and basements typically are much cooler than this. In this project, the dehumidifier installed was a SaniDry Basement Air System which has air filtration built in and is Energy Star rated.
Hi, I'm Bob Villa. Welcome to the show. Our basement finishing project is very far along here in our cottage in Melrose.

Today we are putting down a floor underlayment system that really handles the moisture, and some carpet tiles that create a beautiful pattern.

We're also going to be showing you closet systems, a whole bunch of storage cabinets that are really furniture grade, and we're also putting in a fireplace insert.

Stick around. It's good to have you with us.

Well, there's a lot happening in our basement space today, but before we get into talking about carpets and cabinets that need to be assembled let's recap a little bit, because you know, it's complicated taking an old, crummy basement and turning it into a nice room.

Our Owens Corning Basement Finishing System has provided all the walls and the ceilings, but there's a lot behind the scenes that's very important. And one of the most important parts of the job is making sure that moisture and dampness are gonna, are not going to ruin everything that we're putting in here.

All right, Larry Jeneski's with us now from Basement Systems.
And Dan, you've got the products, and we've been taking a lots, lots of measures here to kind of waterproof this basement area, and this is the latest.


This is the an under-lament, right?

It is. It is a plastic sub-floor made specifically for basements.


And you know, in a basement, it's very important that we don't have organic material on the floor because we have water vapor coming up through concrete...


...that's porous, and we don't wanna have mold underneath the floor.

Well, traditionally, a lot of people would just put down visqueen right over the concrete.
And then on top of that, you could lay down pressure treated 2x3's or 2x4's and you can insulate between, with a rigid insulation, for example, and then on top of that, you could put a regular plywood floor.

Why is this a better system?


Well there is couple of problems with putting this green on the floor and one is that water vapor condenses into water underneath it.

Underneath the plastic, right?

That's right.
And then, another problems is, you know, the basement is a big hole underneath the house that's full of pipes and one day there's gonna be a plumbing leak.

So, the water will line up in the basement and when that wood subfloor gets wet and it's just sitting there saturated the plywood buckles, and mold grows and rot happens and it's just we gotta keep the wood off of a basemen t floor.


You've made the point.

And Dan is into, I mean, he just started in that corner.

So, there's also the efficiency of speed and cost involved here, right?


How do these fit together?

Yeah, they just lock together with a teeth and a ship lock design and that stops the water vapor.
And what we're gonna do afterward is...

So even though I see a kind of a crack there in the grid.

It's interlocking, so that it's visual but it's not actual.

That's right. That's right. That crack doesn't go all the way through there.

That crack doesn't go all the way through.

That's right. Yeah, there's a room for a little expansion and contraction between each tile. And another nice thing about this is it only takes up a half inch of your ceiling height. And in a basement that can be precious.

That's a very good point, yeah. What about the cost? Is it more cost effective than going the old route?

It's about the same.


It's about the same. But you know, this is the last sub floor you'll ever have to install in a basement.

If you do have any kind of a water problem, God forbid , you can come right down here and lift them up and...


And dry it off. And figure out what the source was and then you can put them back down.

You can.

They're not going to be damaged by the damp.

That's right. Water will not affect it at all.

Yeah. Yeah. And what about, is it just gonna lay flat on the slab?

Yeah, usually on a flat floor. It will lay flat and we'll fasten the perimeter tiles so then when they put tact strips for the carpeting, they're pulling against the tack strip when they stretch the carpeting and the The tack strip is fastened to the tile. The tile is fastened to the floor, and everything's good at the parameter.

So, it's a three part system including the underlayment, the pad and then the carpet.

That's right.

And that of course, is gonna muffle any kind of sound that, any sound concerns that you might have, because it is a rigid plastic.

Yeah, well, in this particular case, this is an old house and this floor is wavy gravy.
I mean, it's got undulations , and bumps and little knobs in the concrete. It's not a flat floor, so what we're gonna do is, we're gonna add some extra fasteners where it's necessary to hold it down nice and tight.

And then the last question is, very often people will have to go down and buy a dehumidifier, even though they have taken all these measures to control moisture. They still feel there's damp in there.

That's right.

And the furniture which is going to get ruined or whatever, or mold growth, what do you suggest in terms of dehumidifying space?

Well you need a dehumidification system that's made for basement environments. Most dehumidifiers are rated at eighty degree, sixty percent relative humidity. And at 80 degrees it's easy to take water out of the air because you cool it a little bit and you get condensation.

But in basements we have temperatures that are much cooler, maybe 62 degrees, 65 degrees.


And we need a dehumidifier that is made for that environment. In here, we've installed what we call a Sanidried Basement Air System. And it is a 100 pint per day de-humidification system.

It has air filtration built in.
It's very energy efficient. In fact, it's Energy Star rated. And it will perform very, very well in basements that have the cool temperatures.

Thanks, Larry and this underlame is going to be ready for carpet in no time.

That's right. Yeah.