Concrete Slab Insulation MISTAKE

Hi, I'm Tim Carter, AsktheBuilder.com. It's been almost three weeks since some substantial work

has been done here on the job site and as you can tell by my clothes, they're making a big mistake

fall is in the air and pretty soon we could have some snow. Remember this is not my job. I am not

the builder and if you discover something new in the video consider clicking that thanks text link

that's under the video and realize that any and all revenue that I receive from you I put back

into the channel in getting new equipment or doing whatever I can to

record more videos for you faster. Today I want to talk a little bit about

getting the slab ready to pour, the basement slab. Let's go take a look. If

you remember in some of the earlier videos there were big stacks of this

two-inch thick closed cell foam insulation and they installed it all yesterday. Alright, so it's all down. I know you're getting blasted out by the

sun, but it's all installed and you can walk on it. I'm walking on it now. Pretty

rigid but I want to show you a couple of mistakes they made in my opinion alright Number one they did the right thing and they offset the seams Alright so that a smart thing to do

But look at these big cracks. See these big cracks between pieces

They're there. They're in a few locations. But the problem is, they did not put..

If I was to lift this piece up, they did not put a vapor retarder down underneath

There's no vapor retarder on top of the gravel. And so that means the radon is going to leak right through the gravel, come up through that crack

Yes, I know it might be filled a little bit with concrete, but what's going to happen is this concrete slab is going to get a crack in it

and radon can leak through that crack. All right, if they would put down an ASTM 1745 vapor retarder underneath all of this

that would pretty much block the radon from getting through and force it into the pipes

to where it's eventually going to come up through this pipe here and go up to the roof

But now let's go talk about the bigger mistake. In an earlier video I told you I pretty much figured they would have to do this

The carpenters were here yesterday, they put in four plates. The first three are treated lumber and the top one is not treated

And that is basically the form for the concrete slab So this concrete slab is going to be poured against this treated lumber all the way down And it going to come up probably about halfway on the third one

because I'm guessing that the slab will be four inches thick. But it's a massive mistake. It's a huge mistake

All right, for a host of reasons. Because I had already talked about in a previous video

sorry you're getting blasted out by the bright sunlight. But way over here, the drain tile, any water that comes up underneath this slab, is going to go here

And they put a 90 on it, and there's a really good chance if we go over here

they may have finally extended it out, you know, to the ground here, you know, coming out through this wall

I'd have to go down and see. But the point is water can come up through that slab and get trapped behind those plates

That's going to be a problem. And then what it would do is see these cracks here in the 2x6s

The water will leak through to get to the OSB that I'm sure is going to be on there and whatever

siding and rot that out. It's a nightmare. It should have never been done this way. All right

So they're going to pour this slab probably next week, I would think

I hope to be here, but there's no guarantees. You can see that those cracks in the foam are going to cause a big problem down the road

You may not think it a big deal but in the big scheme of things it is a big deal And it really kind of a shame Just make sure that when you pour a concrete slab either indoors or outdoors maybe you pouring a slab for an

outdoor shed, put a vapor retarder on the ground. Put a vapor retarder on the gravel. All right and

it will stop water vapor from the soil from coming up into the slab. And you want to make sure you

use one that has an ASTM 1745 rating. Don't buy that crappy stuff from the home centers

that's the translucent, crappy, 6mm vapor barrier. It's got all kinds of pinholes in it. It's not

cross laminated. You want the cross laminated ASTM 1745 vapor retarder. Simple as that. Got any

questions? Guess what? I offer phone coaching and I'm happy to help you over the phone. Look for the

description of that in the video. And also remember, if you found something helpful or

discovered something new, think about clicking that Thanks button underneath the video. Every

single dollar that is raised there, I reinvest back into the channel. Thanks very much. I'm

Tim Carter, AskTheBuilder.com. If you want to discover more home improvement tips, go

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