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Wade Carpenter
09-23-2011, 08:48 AM
We are putting up a pole barn, and will have "in floor" hydronic heat (PEX tubing)
From the research and information provided to us, the concrete will be poured on top of XPS foam board and will be poured after the building is erected using the building for the outer form for the concrete.

From what I read, a concrete encased electrode is required for all new installs, and I am trying to figure out what is the proper way to do this with this building. Since the floor/building will not have footers, and the slab itself is not in direct contact with the earth (and from what I read, in the slab doesnt count, would have to be in footers - which wont exist) because of the foam board under slab, I am confused as to what is needed/how it should be done to be safe and meet the requirements.

It will be a 6" slab, in a 40x60 pole barn. I have conflicting advice from concrete and construction people in the area, whether or not the slab will need reinforcement. Some are saying "have to have rebar or wire mesh" (those people have not seen the ground) and others that have been out and seen the ground after the ground work say that its plenty hard and the rebar or wire mesh is optional. So going without mesh/bar in the slab would create a need for something to create the concrete enclosed electrode... and from what I have read, even with wire/rebar, it isnt in a footer and therefore wouldnt qualify as Ufer anyway.

So Im trying to figure out what the right thing to do is. It will be a couple weeks before the building is erected, but the concrete work will follow shortly there after, and I want to have my ducks in a row as to not hold up progress.

Thanks in advance.
Wade

Ted Menelly
09-23-2011, 09:14 AM
A grounding electrode to a grounding rod at least ten feet into the ground

As far as metal in the slab I would suggest you do. There is fairly heavy clay in most of your area and if for no other reason, when the ground moves, the slab will crack but you will not have open cracks or differential settling. No footer in direct contact with earth then a no UFER. Bur in saying that, there is a substantial amount of metal in the slab being a 40 by 60 slab and I for one would like to see it attached to a ground rod and not necessarily the same one.

Just my opinion and as you see even where you are there is varying opinion on the slab and grounding.

I am sure one of the code boys or electricians will chime in and differ as well. It just makes sense to ground all that steel where all the concrete will be wet often and all that steel runs thru it and a ground rod in this situation is the only way to get a good ground to earth.