GEC connection to Ufer

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Is it acceptable to make the connection to the Ufer outside of the concrete? Due to incoming weather, the concrete contractor is speeding up his timeline and I can't be onsite to cadweld the GEC to the rebar before the concrete is poured so the contractor said that he will stub rebar out under his form and I can connect to that. I've never done it this way before and I can't find anything that says I can't, but I'm just not sure. Any help with this is appreciated.
 

don_resqcapt19

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Staff member
Location
Illinois
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retired electrician
List item (3) is new for the 2014 code to address that issue.
250.68(C) Grounding Electrode Connections. Grounding electrode conductors and bonding jumpers shall be permitted to be connected at the following locations and used to extend the connection to an electrode(s):
...
(3) A concrete-encased electrode of either the conductor type, reinforcing rod or bar installed in accordance with 250.52(A)(3) extended from its location within the concrete to an accessible location above the concrete shall be permitted
 

Ponchik

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Location
CA
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Electronologist
yes you can connect it outside of the concrete.

Why do you want to do cadweld?
 

tkb

Senior Member
Location
MA
If the connection was made to the rebar and covered in the footing with concrete it would have to be done by a licensed electrician and inspected before the pour in MA.

If the rebar is installed and stubbed out of the pour for the Ufer connection at a later time during construction, would the rebar have to be inspected by the electrical inspector?

A lot of times the electrical contract isn't awarded until after the footings are started.

FWIW I would Cadweld too. It's a higher quality connection.
 

infinity

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Location
New Jersey
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Journeyman Electrician
Does "extending from its location from within the concrete" include making the connection below grade? Provided that I use a connection that's approved for direct burial.

No, the connection point to the GEC needs to be accessible and above the concrete. From Don's post:

"extended from its location within the concrete to an accessible location above the concrete shall be permitted ".
 

Strathead

Senior Member
Location
Ocala, Florida, USA
Occupation
Electrician/Estimator/Project Manager/Superintendent
List item (3) is new for the 2014 code to address that issue.

One word of advice, you better check with your local inspection department before the pour. In our area, the electrical inspector must see the UFER before concrete is poured, so an inspection would have to be called. They have been nice a few times and warned a concrete contractor, but they are now likely to make them chip the concrete back out.
 
I think that I should have been more clear on the details of the project. This is not a dwelling or a building. This is a large concrete pad used to support a sand & gravel fractional processing plant in the middle of nowhere. The idea was to weld the anchor bolts of the equipment into the rebar and cadweld the GEC to the rebar. Since I can't be onsite before the pour the concrete contractor offered to leave the rebar long from under his forms about 4' below grade. He claims that he has done this several times before. I just have never done it this way, but looking through the code 250.68(A) makes me think that this is ok. I guess my entire question really comes down to whether I can make the connection to the concrete encased electrode below grade outside of the concrete or does it have to be made inside of the concrete?

250.68(A) Accessibility.
Exception No. 1: An encased or buried connection to a concrete-encased, driven, or buried grounding electrode shall not be required to be accessible
 

Fulthrotl

~Autocorrect is My Worst Enema.~
One word of advice, you better check with your local inspection department before the pour. In our area, the electrical inspector must see the UFER before concrete is poured, so an inspection would have to be called. They have been nice a few times and warned a concrete contractor, but they are now likely to make them chip the concrete back out.

they aren't that nice here. if it's not inspected, it's not a UFER.... :happysad:
 

Ponchik

Senior Member
Location
CA
Occupation
Electronologist
As long as the rebar of the concrete is inspected (and verified for a minimum of 20' of rebar) I don't see why you can not connect on the outside of the concrete. It is done all the time.

Now, if you do the GEC connection to the rebar in the concrete, then that HAS to be inspected and verified by the inspector before the pour.

It will also depend how your local AHJ like to do things.
 

don_resqcapt19

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Location
Illinois
Occupation
retired electrician
Does "extending from its location from within the concrete" include making the connection below grade? Provided that I use a connection that's approved for direct burial.
The structural codes do not permit rebar to extend out of the concrete below grade.
 

Ponchik

Senior Member
Location
CA
Occupation
Electronologist
The structural codes do not permit rebar to extend out of the concrete below grade.

But a 20' of rebar (does not have to be continuous) that is connected to the structural rebar can be extended out of the concrete and be used as a CEE.
 

don_resqcapt19

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Location
Illinois
Occupation
retired electrician
If the connection was made to the rebar and covered in the footing with concrete it would have to be done by a licensed electrician and inspected before the pour in MA.

If the rebar is installed and stubbed out of the pour for the Ufer connection at a later time during construction, would the rebar have to be inspected by the electrical inspector?

A lot of times the electrical contract isn't awarded until after the footings are started.

FWIW I would Cadweld too. It's a higher quality connection.
For that very reason we permit (require, if there is not an electrical contractor selected) the concrete contractor to make the connection to the rebar (even where a copper tail is connected to the rebar) The connection and rebar is inspected by the building inspector when the footing inspection is made.
 

RICK NAPIER

Senior Member
Location
New Jersey
For that very reason we permit (require, if there is not an electrical contractor selected) the concrete contractor to make the connection to the rebar (even where a copper tail is connected to the rebar) The connection and rebar is inspected by the building inspector when the footing inspection is made.
Here in NJ the building inspector also inspects this.
 

don_resqcapt19

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Staff member
Location
Illinois
Occupation
retired electrician
But a 20' of rebar (does not have to be continuous) that is connected to the structural rebar can be extended out of the concrete and be used as a CEE.
There is an issue with severe corrosion where the ferrous metal extends out of the concrete below grade. Even if this is not part of the required structural system, the expansion from the corrosion of the rebar can cause damage to the concrete. Also, within a couple of years, you will not have a connection to the concrete encased electrode. That would get a red tag here.
 

tkb

Senior Member
Location
MA
In a footing that has rebar, can you just install 20' of copper and not connect to the rebar?
Can this method be used if you don't have a rebar clamp or Cadweld mold with you?
 

texie

Senior Member
Location
Fort Collins, Colorado
Occupation
Electrician, Contractor, Inspector
There is an issue with severe corrosion where the ferrous metal extends out of the concrete below grade. Even if this is not part of the required structural system, the expansion from the corrosion of the rebar can cause damage to the concrete. Also, within a couple of years, you will not have a connection to the concrete encased electrode. That would get a red tag here.

Yes, this has been a known issue and the 2017 NEC is going to address this in 250.68 with new language that prohibits extending rebar out of concrete below grade or an area subject to corrosion. This will make it clear that if you want to use the method of extending the rebar out of the concrete it will have to be done in a dry area such as inside a dry wall cavity above grade.
 
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