CCE in Flowable Fill

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steve66

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Can Flowable Fill be considered the same thing as concrete for the purpose of installing a concrete encased electrode?

Steve
 
I am not familar with the term "Flowable Fill".

Are you talking about the grout used to fill the hollow spaces of a masonary wall?

Chris
 
http://www.csra.com/ProdsServices/downloads/CIP/17p.pdf

The requirements of 250.53(A)(3) include that the electrode be encased in "concrete".

Flowable fill can have as little as 30 psi compressive strength. It may be little more than sand with some cement and some additives to make it flow better.

Flowable fill is not concrete and is not controlled like concrete. It is sometimes made weak so it can be easily removed. Because it is so weak it can't be relied on to bond to the electrode.

The requirements of 250.53(A)(3) are that the electrode be encased in "concrete". "Flowable fill" doesn't meet the requirements for a Concrete Encased Electrode because it isn't Concrete.
 
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The only concrete encased electrode in the code is in a footing or foundation. You can't use flowable fill to build a footing or foundation.
Don
 
OK, so what do you do when you have a building built on top of this stuff?

I guess it means a concrete encased electrode is not required since the footings and foundation are NOT "in direct contact with the earth".

Steve
 
steve66 said:
I guess it means a concrete encased electrode is not required since the footings and foundation are NOT "in direct contact with the earth".

Steve


???????????? What am I missing here? What circumstance is a footing not in direct contact with the earth???
 
inspector,
What am I missing here? What circumstance is a footing not in direct contact with the earth???
The footing, in this case, is on top of flowable fill and not in contact with the earth. The real question is if flowable fill is earth?
Don
 
If I put a CCE in the footing, and another one in the flowable fill, I think I have it covered no matter how you look at it. (There will also be the good old fashined ground ring around the entire building.)
 
don_resqcapt19 said:
Steve,

The code does not recognize that as a grounding electrode.
Don


OK, but it does not prohibit it either, right.

In this case, I think the "If in doubt, ground it!" theory works.

And 20' of #2 wire isn't that expensive.

Steve
 
Steve,
I'm am sure that it would work ok, but it just isn't a grounding electrode per the NEC. This is just like my proposal to permit a grounding "lateral" that was rejected by CMP5. My proposal said there was no magic in having a 20' ground ring and that if a ground ring is a suitable grounding electrode, then 20' of copper run it a straight line should also be a grounding electrode. They didn't like that idea because I didn't have any testing data to support my proposal. One of the members that agreed with me said there was never any testing data for the 20' ground ring and that my proposal should have been accepted.
Don
 
georgestolz said:
I agreed with your proposal, their premise for rejecting it was very flimsy, IMO.

Flimsy?

Heck their reason does not even make sense. :mad:

Apparently a circle has some sort of Moe-Jo that makes it work better than a straight line.:rolleyes:
 
I have a situation somewhere along these lines...

I just installed a new service on a house along with two new ground rods.
The service is mounted on the rear of the house and the (closest) ground rod is about 12 feet from the Meter/Main.

The job has already been inspected.

The owner is preparing to pour a concrete patio (4" thick, 10' x 40') at the rear of (and attached to) the house.
Before the pour, I'm thinking about bonding the (#5) re-bar in the patio to the (#4) GEC that runs directly under it.

The concrete will be on about 6" of gravel fill with the re-bar at the bottom of the concrete.

I figure that it can't hurt, and may help to provide a better earth ground.

Any opinion...pro or con?

steve
 
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