Ufer as building steel bond?

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cnleek4

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Couple of questions:

1) I always use a ufer ground for my GEC. By virtue of that fact, I do not run a seperate building steel bonding conductor since the steel in the footing which the Ufer is tied to will generally tie into a column pier or grade beam and pick up building steel through a base plate. Am I wrong in this?

2) Having a debate with my field supervisor. He maintains that a cold water bond needs to be connected within 5 feet of the water system's entry into the building. I feel that since we routinely use a Ufer as GEC, and the 5 foot rule applies to using the cold water piping as a GEC, the cold water bond can be made at any accessible location in the piping system.

Any input is appreciated.
 
Re: Ufer as building steel bond?

Sorry, 250.50 Grounding Electrode System. If available on the premises at each building or structure served, each item in 250.52(A)(1) through (A)(6) shall be bonded together to form the grounding electrode system. Where none of these electrodes are available, one or more of the electrodes specified in 250.52(A)(4) through (A)(7) shall be installed and used.
250.52 Grounding Electrodes.
(A) Electrodes Permitted for Grounding.
(1) Metal Underground Water Pipe. A metal underground water pipe in direct contact with the earth . . .

Notice that the metal underground water piping is the first one listed in 250.52. Since the water pipe may have a non-metallic piece installed at some time and it lose its position as a grounding electrode, it must be supplemented. The Ufer ground is a supplement to the water pipe, not the other way around.

The bottom line is that you are required to make the connection within five feet of where it enters the building. :D
 
Re: Ufer as building steel bond?

I am in so. California, and in virtually all new construction in my area, the water mains coming into buildings are plastic pipe and don't transition to copper until they are out of the dirt. IMO this eliminates them as a candidate for GEC in any way shape or form, since no metal is in direct contact with earth. what you have left is strictly the bonding of the cold water piping system to the building ground. I don't have my codebook here with me, (it's at the jobsite), but a cold water bond is allowed in any accessible space.
 
Re: Ufer as building steel bond?

Originally posted by cnleek4:
the water mains coming into buildings are plastic pipe and don't transition to copper until they are out of the dirt.
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You did not say that before. :D

Now I would agree with you, you may bond the water piping system anywhere. ;)
 
Re: Ufer as building steel bond?

250.52 Grounding Electrodes.
(A) Electrodes Permitted for Grounding.
(1) Metal Underground Water Pipe. A metal underground water pipe in direct contact with the earth for 3.0 m (10 ft) or more......
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Your water piping is not a permitted grounding electrode so all that is required is bonding the interior metal water pipe anywhere you want. :)
 
Re: Ufer as building steel bond?

Yes it has to be used if available and it is second in the list of electrodes.


250.50 Grounding Electrode System.
If available on the premises at each building or structure served, each item in 250.52(A)(1) through (A)(6) shall be bonded together to form the grounding electrode system. Where none of these electrodes are available, one or more of the electrodes specified in 250.52(A)(4) through (A)(7) shall be installed and used.
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250.52(A)(2) Metal Frame of the Building or Structure. The metal frame of the building or structure, where effectively grounded.
Click to expand...
 
Re: Ufer as building steel bond?

250.90 General. Bonding shall be provided where necessary to ensure electrical continuity and the capacity to conduct safely any fault current likely to be imposed.

Your case of 'bonding' (250.104(A)), is not performed for the same reason as 'grounding' as per 250.52(A)(1).

Reading 250.4(A)(2)&(3) may help to understand these separate functions a little better.

Pierre
 
Re: Ufer as building steel bond?

Cnleek4,
I do not run a seperate building steel bonding conductor since the steel in the footing which the Ufer is tied to will generally tie into a column pier or grade beam and pick up building steel through a base plate. Am I wrong in this?
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if you can assure this is the case, then the bonding of these two items is already done. The grounding electrodes in 250 can be joined together with a series of jumpers. Iwire posted a picture from the handbook a while back showing this system, maybe he will again.

In any case, take time to read the section as the others have suggested.

Roger
 
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