Grounding Electrode Required?

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amptech

amptech

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Indiana
Here is the situation:
Existing small church with a 200A 1? service. A gym/fellowship hall is being built and will connect to the existing church via 15' enclosed breezeway. The building code requires there to be fire separation between the church and the new addition and declares the addition a separate structure. 2 layers of 5/8" sheet rock are installed on the outside of the wall, under the vinyl siding facing the existing church. Automatic closing fire doors are installed at the new addition end of the connecting breezeway.
The electrical design calls for the original 200A service to be upgraded to a 320A meter-main with 200A feeding the existing panel in the church and 200A feeding a panel in the new addition via a 2-1/2" PVC conduit underground from the meter location to the panel location in the new addition. This route was used to avoid feeding the new building with a feeder passing through the existing building.(230.3). The feeder to the new addition will be 4 wire and a CEE was installed at the panel location in the new addition. EGC and the grounded conductor of the feeder will not be bonded at the new panel and the CEE conductor will terminate in the EGC bar in the new panel.
Here's the problem: The local inspector is forbidding the connection of the CEE to the new panel. He maintains that the breezeway connection makes both buildings one structure. He agrees that a 4 wire feeder is required and the EGC and grounded conductor should not be bonded in the new panel but insists the connection of the CEE or any other grounding electrode to the new panel is a code violation. I maintain that since the building code plan review has determined that the addition is a separate structure, the requirements of 250.32(A) must be satisfied. All NEC references in this post are 2008NEC. Opinions(with NEC reference) wanted.
 
Roger, what happened? I was logged in when I wrote the post but when I went to submit it I was prompted to log in again. Can you remove the one you closed and leave just the active one?
 
I don't think it is a seperate structure either, at least as far as the NEC is concerned.

Regardless, the code does not prohibit you from having supplementary grounding electrodes.
 
I believe it is a separate structure and that you must follow the rules of 250.32. The building code determines if it is a separate structure not the NEC. I think....:wink:
 
From your description the breezeway appears to be a pedestrian walkway constructed in accordance with Section 3104 of the IBC. This section of the IBC provides that "connected buildings shall be considered to be separate structures". These provisions are ofted used where an addition to a building would result in the building being over area for the type of construction involved. It is not unusual to see connected buildings supplied by separate electrical services.

Anyhow, as separate structures, Section 250.32(A) of the 2008 NEC would require a grounding electrode system at the building supplied by the feeder.
 
Sounds like one structure to me. There are fire doors and extra layers of sheetrock in all types of single commercial buildings separating one area from another. Does that make them separate structures? IMO no.


And separate structures or not, where does it say that a subpanel cannot have a grounding electrode connected to the EGC? Did the inspector cite a particular article that prohibits this?
 
The inspector couldn't/wouldn't give a code reference backing up his prohibition of an electrode at the new panel. My position is, even if it isn't required, what would be the harm ? I am sure the CEE is a better electrode than the 1/2" x 8' rod at the original service and if they are tied together isn't that just more better?
 
infinity said:
Sounds like one structure to me. There are fire doors and extra layers of sheetrock in all types of single commercial buildings separating one area from another. Does that make them separate structures? IMO no.


And separate structures or not, where does it say that a subpanel cannot have a grounding electrode connected to the EGC? Did the inspector cite a particular article that prohibits this?
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I thought fire separation in a single structure was 1 hour rated and fire separation between 2 structures had to be 2 hour rated. They required 2 hour on the outside of this addition on the wall facing the original building. I could be wrong. Building code isn't my specialty outside of when it involves the electrical system.
 
amptech said:
I thought fire separation in a single structure was 1 hour rated and fire separation between 2 structures had to be 2 hour rated. They required 2 hour on the outside of this addition on the wall facing the original building. I could be wrong. Building code isn't my specialty outside of when it involves the electrical system.
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It's not my forte either but I see two-hour rated partitions all of the time in commercial buildings and I don't see how that automatically separates one building into many separate structures.

And regarding the additional grounding electrode that may not be required, IMO it's not a code violation to install additional electrodes and connect them to the EGC at a subpanel.
 
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