ufer question for small residential addition

[donselec]

My g.c. is putting a small addition on an existing single-family house to enlarge the kitchen. The house was built in 1979. The service entrance is existing and doesn't need to be upgraded, though I will add a sub-panel next to the main outdoor panel to make space for some new circuits that'll be needed for the remodel. The sub-panel will not be in the addition, but on the existing house. The g.c. asked me if they'll need a ufer ground installed for the rebar in the new foundation for the addition, and I honestly don't know. Any help would be appreciated.

 

[GoldDigger]

My g.c. is putting a small addition on an existing single-family house to enlarge the kitchen. The house was built in 1979. The service entrance is existing and doesn't need to be upgraded, though I will add a sub-panel next to the main outdoor panel to make space for some new circuits that'll be needed for the remodel. The sub-panel will not be in the addition, but on the existing house. The g.c. asked me if they'll need a ufer ground installed for the rebar in the new foundation for the addition, and I honestly don't know. Any help would be appreciated.

If the rebar qualifies as a CEE (UFER) under the current code definition, I would say that you have to connect to it.
Required or not, short of some water pipes and some structural steel it is the best Ground Electrode you can get.

 

[shortcircuit2]

I agree with GoldDigger, all electrodes present at a building must be connected to create your grounding electrode system.

 

[donselec]

I agree with GoldDigger, all electrodes present at a building must be connected to create your grounding electrode system.

Well I know that's true, and it's better to be safe than sorry, but since the service is already existing and not being upgraded or changed, I thought that might make a difference. It'd probably be best though to have the connection available.

 

[donselec]

We talked to the building inspector today, he said as long as the service has 2 existing forms of grounding the ufer won't be required. If we were doing a new service however it would be. You never know though, different jurisdictions may be different.

 

[infinity]

We talked to the building inspector today, he said as long as the service has 2 existing forms of grounding the ufer won't be required. If we were doing a new service however it would be. You never know though, different jurisdictions may be different.

I agree with the inspector. What you're doing has nothing to do with the existing service.

 

[petersonra]

I agree with the inspector. What you're doing has nothing to do with the existing service.

I think the inspector is making it up if he actually said it had something to do with the existing service having two forms of grounding, UNLESS one of those forms of grounding is a CEE. Since this would appear to be an addition to an existing structure it is all one structure and even if the rebar in the new addition qualified as a CEE you are only required to use one CEE if there are multiple ones present.

However, you probably are not required by your jurisdiction to upgrade the service to the latest code just because you put on an addition. That would be like making you add AFCIs in the rest of the house when you put on the addition.

 

[mwm1752]

Once you install the footer with rebar steel you are creating a UFER and should be used & attached to the existing service IMO -- the building is not the same as it was before -- there is no requirements to have rebar in footing unless it is design requires it. If you drove another ground rod it would be required to attach/ new CU water service would have to be attached --

 

[GoldDigger]

Once you install the footer with rebar steel you are creating a UFER and should be used & attached to the existing service IMO -- the building is not the same as it was before -- there is no requirements to have rebar in footing unless it is design requires it. If you drove another ground rod it would be required to attach/ new CU water service would have to be attached --

:thumbsup:

The root of that problem is, as you say, that if you have qualifying rebar in the addition you have created a CEE whether you attach a GEC to it or not.
Then if there is not already a CEE in the original part of the house you would, IMHO, need to connect to it.
If you do not create a new CEE (by using insulated rebar, for example) then the question is moot.
The analogy of having to bond the new GE if you drive a new rod (unless auxiliary) seems appropriate.

 

[donselec]

Thanks. I guess the bottom line is since the service was installed in 1979 there was no UFER requirement, and it's grandfathered in. If we were upgrading the service, replacing it, relocating it, or installing a whole new service, then that new work would have to comply with today's codes and be also connected to the UFER. The inspector's statement about the "2 existing forms of grounding" is probably referring to what was required in 1979. The only other thing to consider in such a situation is that if you ever did upgrade the service in the future, you'd no longer have access to the rebar in the addition, so that might be a concern down the road.

 

[packersparky]

Thanks. I guess the bottom line is since the service was installed in 1979 there was no UFER requirement, and it's grandfathered in. If we were upgrading the service, replacing it, relocating it, or installing a whole new service, then that new work would have to comply with today's codes and be also connected to the UFER. The inspector's statement about the "2 existing forms of grounding" is probably referring to what was required in 1979. The only other thing to consider in such a situation is that if you ever did upgrade the service in the future, you'd no longer have access to the rebar in the addition, so that might be a concern down the road.

There was a reqiurement for concrete encased electrodes to be used if present in the 1978 NEC.
It was found in 250-81(c).

 

[donselec]

There was a reqiurement for concrete encased electrodes to be used if present in the 1978 NEC.
It was found in 250-81(c).

That's true, but I've never been asked, and I don't know anyone's who's been asked to use the rebar system in residential until it became routinely required I think in the 2005 Code. Never thought about that before though. On this particular job I just have to go by the AHJ I guess. Something to think about though.

 

[jaggedben]

Once you install the footer with rebar steel you are creating a UFER and should be used & attached to the existing service IMO -- the building is not the same as it was before -- there is no requirements to have rebar in footing unless it is design requires it. If you drove another ground rod it would be required to attach/ new CU water service would have to be attached --

I don't really agree. A bit of rebar in a foundation does not necessarily constitute a CEE according to the NEC. It's really depends on the details of the design and how much new foundation is being poured, or else it's up to the AHJ to decide how much of a change to the existing building justifies a requirement for a compliant CEE.

Where I live they have a rule that if you add more than a certain amount of new foundation (I think it's 12 linear feet), then you have to install a proper CEE and connect it to the existing service. That strikes me as a reasonable approach. Whether the OP's 'small addition' would qualify is not clear.

 

[kwired]

I don't really agree. A bit of rebar in a foundation does not necessarily constitute a CEE according to the NEC. It's really depends on the details of the design and how much new foundation is being poured, or else it's up to the AHJ to decide how much of a change to the existing building justifies a requirement for a compliant CEE.

Where I live they have a rule that if you add more than a certain amount of new foundation (I think it's 12 linear feet), then you have to install a proper CEE and connect it to the existing service. That strikes me as a reasonable approach. Whether the OP's 'small addition' would qualify is not clear.

You need 20 feet before it will become a NEC qualifying electrode, so what good does 12 do?

If you would already have a CEE connected to the electrical system you don't need to add additional CEE's to the electrical system just because they were added to the structure, nothing prohibits bonding to them either though.

 

[jaggedben]

You need 20 feet before it will become a NEC qualifying electrode, so what good does 12 do?

One can easily connect 20 feet of rebar within 12' of foundation, or use copper wire. Anyway the 12' number might be incorrect, that is incidental to the point.

If you would already have a CEE connected to the electrical system you don't need to add additional CEE's to the electrical system just because they were added to the structure, nothing prohibits bonding to them either though.

In the jurisdiction I'm talking about most buildings are too old to have had a CEE when built. (To be clear, if there's already a CEE the rule I mentioned does not apply.) In the OP's case it is not clear if there is already a CEE connected to the service or not.

 

[kwired]

One can easily connect 20 feet of rebar within 12' of foundation, or use copper wire. Anyway the 12' number might be incorrect, that is incidental to the point.



In the jurisdiction I'm talking about most buildings are too old to have had a CEE when built. (To be clear, if there's already a CEE the rule I mentioned does not apply.) In the OP's case it is not clear if there is already a CEE connected to the service or not.

So if you have service on one end of a large building and put a small addition on the point furthest away from the service they make you tie the added CEE into the existing electrical system?

I guess it might not be that hard if the building has structural steel throughout and you just installed a bonding jumper from steel to the added CEE, but a building with no steel would mean running all the way back to the service or main disconnect for a feeder supplied building.

 

[jaggedben]

So if you have service on one end of a large building and put a small addition on the point furthest away from the service they make you tie the added CEE into the existing electrical system?

I guess it might not be that hard if the building has structural steel throughout and you just installed a bonding jumper from steel to the added CEE, but a building with no steel would mean running all the way back to the service or main disconnect for a feeder supplied building.

Yes, they do, and yes, it's a bit stupid sometimes. Generally the buildings we're talking about are wood frame with no structural steel.

 

[packersparky]

So if you have service on one end of a large building and put a small addition on the point furthest away from the service they make you tie the added CEE into the existing electrical system?

I guess it might not be that hard if the building has structural steel throughout and you just installed a bonding jumper from steel to the added CEE, but a building with no steel would mean running all the way back to the service or main disconnect for a feeder supplied building.

I see no difference if a metal underground water pipe was added to a building. Its a grounding electrode, and around here that would have to be connected to the grounding electrode system.

 

[kwired]

I see no difference if a metal underground water pipe was added to a building. Its a grounding electrode, and around here that would have to be connected to the grounding electrode system.

If no additional electrical work is to be done, no electrical permit is even filed, who ensures it gets done?

Nothing wrong with adding those electrodes, but big brother doesn't need to stick his nose in every detail all the time IMO.

 

[Strathead]

I see no difference if a metal underground water pipe was added to a building. Its a grounding electrode, and around here that would have to be connected to the grounding electrode system.

There is a difference. The underground water pipe comes out of the ground. If the copper stopped 24" under cover and the copper was changed to PVC coming out, then you would be required to connect it. I don't see where an AHJ could require you to install a UFER if you aren't required to upgrade the service. That said, I would install one anyway, if it was my house.