Is this one building or two?

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gary

gary

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Location
California
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Retired electrical contractor / general contractor
I'm working on a new custom 2500 sq. ft. two story house on a raised foundation that is 5 feet away from a 3-car garage on a slab. The house & garage are to be permanently connected together by a covered breezeway. The roof will run in one continuous plane across the garage and breezeway and a portion of the main house. I plan to put the service in the garage and run the house circuits through the roof structure joining the two parts of the building. I thought I had installed a more than adequate Ufer ground when I ran 35 feet of bare #4 wrapped along the bottom rebar. I did that because the phone service was to be located away from the electrical panel & thought I'd bring one end up into the electrical panel and the other end up to the phone service box. When the building inspector checked the footings today, he told the general contractor that the county considered this to be two separate buildings because there was no continuous footing joining them together. Because this is two separate buildings, he claims there needs to be two separate Ufer grounds. I don't know what I'm supposed to connect this second Ufer ground to, but they're pouring the foundation tomorrow morning & the general wants me to go out before 7AM and put in a piece of wire to get the building department off his back. We've done similar projects in the past without this ever being an issue. Am I the only one who thinks this is foolish nonsense?
 
The real question is, is it an occupancy or group of occupancies?! ;)

(Sorry about that. I can't help you here at all. I'm sure the IBC has a definition of "Building", and IMHO the continuous roof makes it one building, but someone with a copy of the building code can probably tell you the actual definition...)
 
Gary,

Is there 1/2" re-bar or larger in the footings? If so, and they are in direct

contact with the earth, run a #4 solid cu. and tie it to a 20' lenght of re-bar.

As for the 'seperate structure' thing, I would say the 'norm' is that when the

roof is built as you described, it is usually 'one' structure. IMSO.
 
Mr

Mr

benaround said:
Gary,

Is there 1/2" re-bar or larger in the footings? If so, and they are in direct

contact with the earth, run a #4 solid cu. and tie it to a 20' lenght of re-bar.

As for the 'separate structure' thing, I would say the 'norm' is that when the

roof is built as you described, it is usually 'one' structure. IMSO.
Click to expand...

Yes, there are two 1/2" bars near the bottom of the footing, two more near the top of the forms, and "U" shaped vertical bars at 4' o.c. to tie everything together. 250.52(3) requires us to use a concrete encased electrode if one is available. My 35' of #4 CU should satisfy that requirement by itself. If I had attached a piece of #4 CU long enough to reach the panel ground bar to one of the bottom rebars, that also should have satisfied the requirement. In this case, there are two separate foundations containing steel that could be used as part of a grounding electrode, but I don't see anything in 250.52(3) that says that all available rebar in a structural footing must be bonded together to form a compliant electrode.
 
I'm not aware of anything in the building code that determines in black and white whether the structure(s) you are talking about are one or two buildings, but I would tend to agree that the continuous roof makes them one building.

This makes me wonder however, if a continuous roof doesn't create one building and a continuous footing is required for it to be one building, how many buildings are there in a pole barn? :D
 
If both buildings have adequate foundation at or below the local frost level, then I would consider it as one building. How would you handle a post framed building (around here called pole barns) that have individual holes drilled for each post. I believe that the concrete encased electrode you described is adequate for the building you described.
 
Maybe I am missing something (my wife says I miss allot)!

Who cares how many buildings it is? You install a grounding electrode for the SERVICE. We are not grounding the building (the building is already fairly well connected to the EARTH!)

You have one electrical service and you have installed a UFER ground for that service. End of story - job done - go to the next item of business.

What am I missing?
 
haskindm said:
Maybe I am missing something (my wife says I miss allot)!

Who cares how many buildings it is? You install a grounding electrode for the SERVICE. We are not grounding the building (the building is already fairly well connected to the EARTH!)

You have one electrical service and you have installed a UFER ground for that service. End of story - job done - go to the next item of business.

What am I missing?
Click to expand...

I agree, but just so I answer you question we would consider it one building, because of the roof. Of course you would still have the 1 hr seperation which would have to go all the way up to the bottom of the roof.
 
haskindm,

I'm guessing that the inspector, after considering the house and garage to be two separate buildings, is then going to 250.32 and using that to require a grounding electrode system for each building. Thats just a guess, and I may be missing something too.
 
I see where that may come into play. Is there a seperate disconnecting means required for this separate building also?
Nothing is ever easy!
 
Oh yeah... once you go so far as to call them two separate buildings (which i wouldn't) then there are other issues to deal with. The disconnecting means that you mention or 225.30 to name a couple.
 
Gary,

It does say, all available G.E.'s shall be connected together to form the

Grounding Electrode System, it would be hard to convince someone that

you don't have two seperated CEE's available ?

Gary, I would have second thoughts on the way the Telco ( bonding ) is

really an electrode, the reason is that if you had a lightning event at or near

this location, one job of the G.E. is to direct lightning into the earth, but with

two potential differances the lightning has a chance to " jump " and cause

damage. That is just an opinion and may not be 100% correct.

The big problem on this job is the two structures interpertation by the EI,

this has to be cleared up before you can wire the place in a compliant manner.
 
I have wired many homes in this county in the past where the house and garage were separate except for a roof structure that joined the two and formed a sheltered breezeway. These projects were always considered one building and one CEE at the service sufficed for the whole structure. This requirement for a continuous footing is new. They actually made the builder take out two separate building permits! In hindsight, a single 5' long footing joining the foundations would have eliminated the problem. As it is, I must assume that I will be required to install a sub-panel with a main breaker at the house side of the breezeway. Fortunately this happens to be a laundry room so it's not a bad place for a panel. And it will have it's own CEE. :cool:

Here's a not so great photo of the front elevation from the plans:
http://i265.photobucket.com/albums/ii217/ac6eg/DSC08712.jpg
 
I would stick to calling it a single structure - on top of grounding - how many other things pass between, like branch circuits? How 'bout water? Other metallic paths? But if you have the oprotunity for a ufer in both - why not do it and argue later? And while you're there - ask about which foundation might settle lower - and wouldn't it be a pity if one lowered much more than the other.... :D
 
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