I went to a new home show today and saw the demo slab on this product.
Check out the web site and watch the picture for the animation.
SlabTek
This was installed in high end luxury homes.

__________________
Jim Luttrall
Mr. Inspector.net, Inc.
Allen, Texas 75002

hmmm...

What raises and lowers the slab?

I bet they'd work great up there in the metroplex soils.

It has more animation deeper into the web site. Looks like typical screw jacks.

__________________
Jim Luttrall
Mr. Inspector.net, Inc.
Allen, Texas 75002

What about the void below the slab?

Boy, the termites is going to enjoy this. This is the worst thing I can see from a termite control point of view. That complete void below the house will have to be completey foamed with a termiticide when an infestation occurs.

Forget about a pre-treat of the soil, it just doesn't hold up that well with the chemicals available.

How about ground water seepage coming up underneath the slab. Ground water or a spring will find those voids. We have springs out here in the Rockwall area near the lake horribly. You can lift up any object on the ground even in the summer months and find water on the surface of the ground.

Just my thoughts,
rick

Rick,

That would be no different that treating for a crawlspace, provide it was lifted high enough ... which brings me to my questions ...

"
Slabtek Slabs are poured on top of the ground and then raised above the ground to a desired height, with patent pending lifting mechanisms. Using the ground as a form is a very economical process, much like commercial tilt-wall construction.

Slabtek Slabs are engineered whereby the same lifting mechanisms used to lift the slab can be used to adjust the height of the slab in the future, if this is ever required.
"

Okay, you have the underground plumbing, electrical, and HVAC (basically the refrigerant and condensate sleeves) installed, you construct the slab, then go to raise the slab ... unless you are using really oversized sleeves, and then they would need to be sealed well to keep out moisture and termites.

What happens to all of those pipes if the sleeves do not move freely? They get pulled up out of the soil? There goes the plumbing sewer pipe slopes.

It's kind of like what I've always asked about expansive and unstable soil - why not build on pilings using elevated slabs (post tension), in fact, it's the same thing I've always said, except for the 'use the soil as the form then raise it' part.

Here's some problems I see with it as designed (and I'm not an engineer either):

The ONLY THING holding the lifting sleeve to the slab are two little 'bolts' sticking out two sides.

I don't see how, as shown in the photo 'Slabtek before concrete is poured' those lifting AND SUPPORTING sleeves will not 'punch through' the slab.

No moisture barrier on the ground?

No sleeve on the pipe shown in that photo.

The sides of that 'column cap' looks like they should have been tapered at 45 degrees.

There is not much steel at all in that column cap.

Oh well, without the engineered PT and reinforcing layout, no inspection can be done.

Another thought: how high can you lift the slab on those skinny little threaded rods before the slab starts to sway in the breeze and then falls over?

__________________
Jerry Peck, Construction / Litigation Consultant
Ormond Beach, Florida
Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )

I have spoken with Childress at length regarding theses slabs. I currently have a project where the homewoner is considering using this technique. I'll let you know how it turns out - if it happens.

Aaron