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#178951 - 06/17/08 03:14 PM Ufer Ground installation
Up2code Offline
Member
Registered: 05/15/07
Posts: 55
Loc: Missouri
Hope everyones having great summer! It seems to fly by. My question is how to properly install a UFER ground, aka foundation ground. General contractor pouring foundation on this house says he's never heard of it. We've decided where service(200A single phase) is going on building, but I've never actually installed one. Any info would be appreciated. Thanks!
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#178961 - 06/17/08 08:02 PM Re: Ufer Ground installation [Re: Up2code]
twh Offline
Member
Registered: 03/11/04
Posts: 901
Loc: Regina, Sask.
Google "ufer ground" with the quotes. There is conflicting information about how it should be done. Such as tied or welded re-bar and about installing bare ground wires in concrete. You might still need the normal ground.
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#178963 - 06/17/08 08:27 PM Re: Ufer Ground installation [Re: twh]
leland Offline
Member
Registered: 08/20/07
Posts: 853
Loc: Lowell area, Ma. USA
Really quite simple. Just run the re-bar from the footings (not foundation) up and out next to the panel (it can go in the foundation walls)(non coated re-bar). Bond that to the panel, done.
That's the simple version... no that's the only version.

The re-bar is now your ground. Anything after that is "supplimental" or bonding.


Edited by leland (06/17/08 08:32 PM)
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#179014 - 06/21/08 06:18 AM Re: Ufer Ground installation [Re: leland]
electure Offline


Member
Registered: 12/24/00
Posts: 4259
Loc: Fullerton, CA USA
It's called a concrete encased electrode, and lives at 250.52 (A)(3) in the 2005 NEC.

Quote:
That's the simple version... no that's the only version


Well, it's not really the only acceptable version.
____________________________________________________________

......"or consisting of at least 6.0 m (20 ft) of bare copper conductor not smaller than 4 AWG."

From the period 1942-1960, H.G. Ufer tested 24 buildings in Arizona every 2 weeks for resistance values. The installations consisted of 1/2" steel reinforcing bars encased in the bottom of the footings. As a result of these tests, Ufer recommended that a #4 or larger copper conductor be encased in the bottom of the footings, and further testing be performed. The results of the further testing impressed the members of CMP-5, and the concrete encased electrode was accepted.

The term "Ufer Ground" truly only applies to this copper electrode, but has generally been used for any concrete encased electrode.



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#180869 - 09/13/08 08:51 PM Re: Ufer Ground installation [Re: electure]
gfretwell Offline


Member
Registered: 07/20/04
Posts: 9038
Loc: Estero,Fl,usa
Make sure your AHJ accepts the turned up rebar method (a piece of rebar above the concrete that is lapped and tied to the steel in the bottom of the footing).
The method that is more universally accepted is a piece of #4 copper tied to the Rebar with a listed clamp and brought all the way to the panel. You always have the fear that this will be broken or stolen between the footer pour and the electrical final though.
In my area of Florida they go with the turned up rebar method and that rebar is in a block cell with a mud ring and cover to keep it accessible.

http://esteroriverheights.com/electrical/ufer.jpg
_________________________
Greg Fretwell
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