NEC 250.52(3) concrete-encased electrode

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cary

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A builder is concerned that due to the new requirement in Va. , if there is reinforcing steel in the footing of a new building it must be used as the grounding electrode. The builder will need to wait for an inspector to check the electrode attached to the steel before concrete is placed for the footing. He is asking if a steel "stick-up" attached to the footing steel can be stubbed out above the concrtete slab from the footing steel and then attach the grounding electrode conductor to the steel stub-up.
I said no that the attachment of the G.E.C. to the footing steel in contact with the earth must be incased in the concrete within the footing.

Any thoughts?:
 
What you have described is very common. I see rebar stubbed up in an accessible spot used for the CEE all the time.

By the way welcome to the forum.:)

Chris
 
Thanks. So the CEE can be attached above the footing as long as the steel is tied to the reinforcement in the footing?
 
cary said:
Thanks. So the CEE can be attached above the footing as long as the steel is tied to the reinforcement in the footing?
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Correct, the connection between the GEC and the CEE does not have to be in the footing. Remember that if the connection is not encased in the concrete then it must be accessible.

Chris
 
How would someone know if there is 20' of tied rebar if they only inspect the stub after the footing is poured? Can they see through the concrete?
 
infinity said:
How would someone know if there is 20' of tied rebar if they only inspect the stub after the footing is poured? Can they see through the concrete?
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This should take place at the footing inspection IMO... Pretty easy around here since 1 guy inspects all trades... :roll:
 
raider1 said:
Correct, the connection between the GEC and the CEE does not have to be in the footing. Remember that if the connection is not encased in the concrete then it must be accessible.

Chris
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Why does it have to be accessible? Do you mean for inspection?
 
guesseral said:
Why does it have to be accessible? Do you mean for inspection?
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The connection between the grounding electrode and the grounding electrode conductor must be accessible, unless buried or encased in concrete. (See 250.68(A))

So if you turn up a piece of rebar that extends the CEE up out of the slab or foundation to make you connection, the connection must be accessible.

Chris
 
raider1 said:
The connection between the grounding electrode and the grounding electrode conductor must be accessible, unless buried or encased in concrete. (See 250.68(A))

So if you turn up a piece of rebar that extends the CEE up out of the slab or foundation to make you connection, the connection must be accessible.

Chris
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So until it is inspected. Then it can be burried. All I could visualize was a 5' rebar sticking up along the block out of the ground!
 
guesseral said:
So until it is inspected. Then it can be burried. All I could visualize was a 5' rebar sticking up along the block out of the ground!
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No, it always has to be accessible unless it is encased in the concrete.
 
iwire said:
No, it always has to be accessible unless it is encased in the concrete.
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No
exception No. 1: An encased or buried connection to a concrete-encased, driven or buried grounding electrode shall not be required to be accessible.

So once made and inspected it can be burried, same 2005 and 2008.
 
iwire said:
No, it always has to be accessible unless it is encased in the concrete.
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Agreed, I typically see a stub of rebar out of the top of the foundation in the wall of the garage. Then a double gang p-ring installed at the connection point so that a double gang blank can be installed after the sheetrock is hung.

Chris
 
guesseral said:
exception No. 1: An encased or buried connection to a concrete-encased, driven or buried grounding electrode shall not be required to be accessible.

So once made and inspected it can be burried, same 2005 and 2008.
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I disagree with your use of that exception for the connection we are talking about.

Most places require something along the lines that Chris described.
 
iwire said:
I disagree with your use of that exception for the connection we are talking about.

Most places require something along the lines that Chris described.
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What most places require isn't always what the code states. ( Sorry that isn't ment to be as cocky or rude as it sounds) The handbook (05 don't have 08 yet) States
When the exposed portion of an encased, driven, or buried electrode is used for the termination of a grounding electrode conductor, the termination must be accessible. However, if the connection is burried or encased, terminations are not required to be accessible.
It goes on to talk about listed connectors but it dosen't ever lead us to beleive any differently.

This is always the way I have looked at this and the way my inspectors have also, I never gave it a second thought and I still don't. I guess this is why we have forums.

So I disagree to your disagreement of my use of the exception. The first part of the handbook explanation verifies it for me. Could be wrong......have been before......will be again. This is just what the code say's.
 
There is nothing in the NEC that states the CEE can't be extended out of the concrete and the connection between the electrode and the electrode conductor be made outside of the concrete. That is what the original post was refering too. So if I extend the footing rebar out of the foundation to make my connection the connection must be accessible. If I choose to make the connection in the concrete of the footing then exception #1 to 250.68(A) would apply.

It isn't very common anymore in my area to run #4 copper for the CEE and stub it out of the foundation due to copper theft. If you do stub up copper it won't be there the next day.

Chris
 
guesseral said:
What most places require isn't always what the code states. ( Sorry that isn't ment to be as cocky or rude as it sounds)
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It was not and you are of course 100% correct.:smile:

In my opinion the rebar brought out of a concrete footing is not 'the electrode' the electrode only exists inside the footing near the bottom of the footing.
 
This is my concern. Since a third party typically inspects footings in our area, and the builder is appealing my decision that he does not want to now wait for an electrical inspection of the Ufer, he wants to have a piece of reinforcement steel stuck up through the footing in order to attach the GEC.
I am concerned that the piece of rebar is not attached to the footing steel. In my expereance in commercial inspections--I always looked at the connection of the GEC attached in the footing--then the concrete was poured. This is a residential builder that is asking to continue on with the concrete by having the re-bar stick above.
There has been a state amendment to the NEC and IRC that if steel reinforcement is required in the footing--the CEE must be used as ground.

My interpretation is similar to iwire--that the connection needs to be made to the footing steel and be encased.
 
iwire said:
It was not and you are of course 100% correct.:smile:

In my opinion the rebar brought out of a concrete footing is not 'the electrode' the electrode only exists inside the footing near the bottom of the footing.
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See in my opinion the rebar brought out of the footing is an extension of the electrode, which the grounding electrode is then connected to. So we can agree to disagree it depende on interpritation and the only one that counts is the AHJ for the area.

I personally do not like the whole idea of extending the rod out of the footing anyway's, I reallize this is the way it is done many places but I prefer the wire method. (I do realize in some places they steal it) My reasoning is that this is now your main grounding electrode and in several years it's gonna rust off and all that is left is the wire! So we have just shot ourselves in the foot we should have just installed a ground rod in the first place. The new wording was suppose to help increase the grounding not decrease it. Because I am sure the GC's are not meeting the requirements of a pipe or rod electrode when they stub out of the concrete, like min 5/8" (maybe) stainless steel (no way) nonferrous (not!). I like the idea of the concrete encased electrode requirement, just not the stub out because I don't think it is right with code. Oh well just my opinion i'll shut up now!
 
guesseral said:
See in my opinion the rebar brought out of the footing is an extension of the electrode,
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Where can I find that thought in description found in 250.52(A)(3). :)



So we can agree to disagree it depends on interpretation and the only one that counts is the AHJ for the area.
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Yes that is the fact.:)

I personally do not like the whole idea of extending the rod out of the footing anyway's,
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Neither do I an I think some structural engineers might take issue with that as well. It introduces a way for rust to start working its way into the footing quicker then it normally would happen.



Oh well just my opinion i'll shut up now!
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99% of what is on this forum is just opinion, no need to keep it to yourself. :smile:
 
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