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Stem Walls, Slab, and Reinforcement for Concrete Walls

After seven days of steady rain, the crew is ready to pour the concrete for the foundation and slab at the Punta Gorda, Florida, storm-ready home. Bob explains how code now dictates that foundations be elevated and supported by a three-course block stem wall set on reinforced footings below the grade. These perimeter stem walls are reinforced with horizontal and vertical number five diameter steel rods or rebar. The stem walls and slab are poured as one to create a seamless slab and foundation. This integral foundation will protect against water intrusion and hydrostatic prssure that lifts slabs and compromises structures when storm surge comes. The concrete is floated and polished to finish the slab before the reinforcing steel rods and mesh are set for the walls. Vertical steel rods are spliced to the reinforcing rods protruding from the foundation, then steel mesh is attached with wire to the rods. Stirrups and rebar create the headers, and spacers are attached to the mesh to keep it centered in the new wall once the concrete is poured.

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Chapters from this episode

Removing the Concrete Wall Forms and Planning the Plaster Finish Now Playing

Removing the Concrete Wall Forms and Planning the Plaster Finish

Building Reinforced Concrete Storm-Ready Homes in Florida Now Playing

Building Reinforced Concrete Storm-Ready Homes in Florida

House Failures in Hurricanes Now Playing

House Failures in Hurricanes

Setting Aluminum Forms for Concrete Walls Now Playing

Setting Aluminum Forms for Concrete Walls

Stem Walls, Slab, and Reinforcement for Concrete Walls Now Playing

Stem Walls, Slab, and Reinforcement for Concrete Walls

A Concrete House for a Hurricane Zone Now Playing

A Concrete House for a Hurricane Zone

Clip Transcript For:

Stem Walls, Slab, and Reinforcement for Concrete Walls

computer-generated transcript - may not be 100% accurate

" Summertime weather in southwest Florida often means afternoon showers but. This time around here in punta gorda we've had seven days of uninterrupted downpours which have finally just abated and today we are. Pouring our concrete slab now much of the preliminary work that's had this. Take place here involved bringing in truckloads of fill so that we could get up to an elevation that meets current requirements. And putting in a new slab for the house is not as easy as it was was his requirements now. Dictate that you build a stem wall around the whole perimeter of the house this means that you're going down about. Three courses of concrete blocks so that you create a barrier to storm surge waters preventing them from getting in underneath. A slab and creating the hydrostatic pressure which could move the slab and in fact destroy the house now. All the concrete that was poured in here which took about three to four hours to get in place was delivered via a big pumping rig. The big Johnson over here. And this makes it very easy to move the concrete around the whole footprint of the house to minimize the amount of labor involved. Now the important thing to keep in mind is that the reinforcing. Is very very very important to the strength of the slab. And so we have to make sure that they're lifting it so that it. Floats in the middle of the slap. And once all of this pouring has been done the finishing begins we use obviously. Bow floats and motorized floats in there we go through stages of finishing and polishing the concrete. The solid wall system itself requires the construction of an elaborate web of steel reinforcing rods. Vertical rebar usually number five's horizontal pieces for heading off window openings in and all of it is covered in steel mesh. What looks like a steel mesh reinforcing. All of this took. Basically about four -- five hours to get accomplished."

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