Pouring the Foundation and Starting the Walls

Bob and Howard discuss the concrete mesh used in the foundation that saved time and materials. Bob reviews the upcoming episode during which first floor walls are built.

Clip Summary

Howard and Bob talk about the steps saved in pouring the slab and about Insul-Tarp which acts as a barrier to the moisture below the slab and provides insulation that prevents heat loss. The haunched footings, the slab, and any reinforcing are all done in one step. Traditionally, a 10'x10' steel reinforcing mesh would go down before the concrete is poured, but that step was eliminated by blending the fibers into the concrete mix. Although the mesh adds to the cost of the concrete, this method is still much cheaper than the traditional one. After the concrete has been poured and allowed to set, the diagonals are checked to make sure the slab is completely square and points are perpendicular. Bob also talks with Ron Ardres of ReddiForm about the ReddiForm insulated concrete form (ICF) system that was used for the foundation walls. The ReddiForm blocks are lightweight and made of expanded polystyrene, a material similar to that used for drinking cups but with added flame retardants. ReddiForm's no-tie rebar chair is being placed on the tops of the forms to prepare for the rebar dowels that will connect the walls to the foundation. Holes are drilled into the slab to install sections of rebar through the ReddiForm blocks. These pieces of rebar tie the walls to the existing slab. The walls will be seven and a half feet high with a structural slab or upper floor placed on top. The walls and the first floor slab will all be poured in one pour.
So Howard, the slab was poured at the same time as the footing was poured. You've really saved a lot of steps here, haven't you?

Yeah, a very streamlined process. The footings are integral with the slab, is referred to as a monolithic slab .


And what's, what's underneath the slab?

We put an Insul-Tarp product that, it combines as a vapor barrier and insulation. We found it at radiantmax dot com.

And what's it actually doing for us?

It, it provides a barrier between the moisture that would be below the concrete slab.

It also provides an insulation value , an R6 or R7 insulation value, that prevents the heat loss from the space below.


No, this is really awesome, though, because you're pouring the footings and the hunch, and the slab and any reinforcing along the middle for the ridge wall, et cetera, all in one step.

It was very efficient.

Now, Howard, traditionally we use a ten by ten reinforcing mesh, a steel mesh that goes down before we pour our concrete slab.

You're not doing that here.

No, we were able to eliminate that by replacing it with the fiber mesh reinforcement that's actually placed at the ready mix plant. It is small fibers that are actually blended in with the mix.

So it's in as an agregate.



Does that add to the cost of the concrete?

I assume it adds a little bit.

Not significantly?

Not significantly. It's still much cheaper than a traditional mesh.

And what about the thickness of the slab?
Do you have to pour it thicker? No, it's a still a foreign slab, but functions the same. It's pretty much like mixing fibers and with any kind of products, when you mix plaster and horsehair. Same basic premise.

And what are the guys doing right now?

We're checking the diagonals to make sure that when we place the walls that it's very square. And everything, and the points are perpendicular.

Ron Ardrus is with us now and he's developed this ready form system.
Ron, what are these made out of?

They're made out of expanded poly-styrene. They weigh nothing, it's just like a drinking cup material, right?

Exactly. The same material that, except this material is modified for flame retardant.

Okay, so the idea is that we will build this up to whatever our height is and then pour concrete in them.

Yes sir.

Now what's this man putting down?

This is our no tie re-bar chair, this will allow us to build the entire wall and drop the steel into that without tying it.

Okay, I can see it over here.
What you're doing then is you're drilling into the concrete slab to install these sections of rebar.


Right through there.


That ties the wall to the existing slab.

Exactly, and they're for sheer off the wall, off the footing.


And so how high is this going to be?

This is going to be seven and a half foot high, the first floor. And then we're gonna incorporate a structural slab on top of it.

So that we'll be pouring the wall and the first floor slab, all in one pour with a different type of form?

Yes, we're going to use a foam form that goes across form this wall to the back wall as a structural slab and it has t beams in it, and that gives us the strength.

I can't wait to see it, but we're running out of time. 'Till next week I'm Bob Vila, thanks for joining us.