dcsva@aol.com
Senior Member
- Location
- Virginia
Would someone please explain a UFER and how you connect to it. I just don't know if I could explain it to someone if I were asked.
UFER
- Thread starter dcsva@aol.com
- Start date
- Status
G
Guest
Guest
Re: UFER
The Ufer ground relies on the building concrete as a sink for the GES (Grounding Electrode System). The Ufer ground is named after Mr. Ufer who developed it. If done right it is supposed to be a better ground than a driven ground rod. The alternative was for Ufer to drive ground rods hundreds of feet deep in the desert (due to the poor soil conductivity). Ufer ground was designed to run in the 5 Ohm range.
Ufer clamps (the clamp from the daylighted rebar to the copper jumper to the service entrance) must be rated for rebar. The Ufer must have at least 20 feet of continuity. It can be #4 rebar, or copper wire in footing:
NEC 250.52(A)(3), 250.70, 255.66(B), 250.24(A)(1), 250.56,
Here are links with more details. Post back with questions:
Google Ufer+ground
../Wayne C.
PS: In new construction assuming residential with a garage your service entrance might be at the front corner of the garage. Depending on who's doing it and what the AHJ says about the specifics here's what I used to do (I've been away from the trades for a while so keep in mind my methods are dated, dusty, and rusty): Take a 20' #4 rebar and bend a 90 degree bend in it about 2' long. Run the 18' towards the back of the garage footing, then stub the 2' section up into the wall right below the service entrance. Now there's only 18' of rebar in the concrete (20' min. required) so I would tie or clamp that rebar to the next rebar to extend the 18' onto the next piece. The fussy guy I am I would also make a good tight bond or use a clamp to tie this 20' section to a couple of the rebars coming up out of some pier holes. This gets the Ufer into some good damp concrete. It's probably unnecessary but it made me feel more like the Ufer was an earth ground. Pure a mental exercises, but I did it anyway. Finally you clamp onto the rebar stub with an approved clamp to jumper a piece of copper up into the N-G bus in the service entrance. Oh, and to make the clamp accessible I put a plaster ring on the garage wall if the wall is to be closed in by drywall. That way you can get to the clamp for inspection or to tighten it. Am I clear as mud? Post back with questions. Somebody probably has a picture that would alleviate these 1000 words of mine
[ September 10, 2003, 01:14 AM: Message edited by: awwt ]
The Ufer ground relies on the building concrete as a sink for the GES (Grounding Electrode System). The Ufer ground is named after Mr. Ufer who developed it. If done right it is supposed to be a better ground than a driven ground rod. The alternative was for Ufer to drive ground rods hundreds of feet deep in the desert (due to the poor soil conductivity). Ufer ground was designed to run in the 5 Ohm range.
Ufer clamps (the clamp from the daylighted rebar to the copper jumper to the service entrance) must be rated for rebar. The Ufer must have at least 20 feet of continuity. It can be #4 rebar, or copper wire in footing:
NEC 250.52(A)(3), 250.70, 255.66(B), 250.24(A)(1), 250.56,
Here are links with more details. Post back with questions:
Google Ufer+ground
../Wayne C.
PS: In new construction assuming residential with a garage your service entrance might be at the front corner of the garage. Depending on who's doing it and what the AHJ says about the specifics here's what I used to do (I've been away from the trades for a while so keep in mind my methods are dated, dusty, and rusty): Take a 20' #4 rebar and bend a 90 degree bend in it about 2' long. Run the 18' towards the back of the garage footing, then stub the 2' section up into the wall right below the service entrance. Now there's only 18' of rebar in the concrete (20' min. required) so I would tie or clamp that rebar to the next rebar to extend the 18' onto the next piece. The fussy guy I am I would also make a good tight bond or use a clamp to tie this 20' section to a couple of the rebars coming up out of some pier holes. This gets the Ufer into some good damp concrete. It's probably unnecessary but it made me feel more like the Ufer was an earth ground. Pure a mental exercises, but I did it anyway. Finally you clamp onto the rebar stub with an approved clamp to jumper a piece of copper up into the N-G bus in the service entrance. Oh, and to make the clamp accessible I put a plaster ring on the garage wall if the wall is to be closed in by drywall. That way you can get to the clamp for inspection or to tighten it. Am I clear as mud? Post back with questions. Somebody probably has a picture that would alleviate these 1000 words of mine
[ September 10, 2003, 01:14 AM: Message edited by: awwt ]
big john
Senior Member
- Location
- Portland, ME
Re: UFER
I thought you were being sarcastic when you said it was designed by a guy named Ufer. I always thought it was a variant of the acronym for Under Footing ground [UF-er].
Learn something new every day.
-John
I thought you were being sarcastic when you said it was designed by a guy named Ufer. I always thought it was a variant of the acronym for Under Footing ground [UF-er].
Learn something new every day.
-John
G
Guest
Guest
Re: UFER
As did I when I first heard it. Or, that it was bent in the shape of a ufer, or such. It sounds like something you might run into when you are on a snipe hunt or out trying to find some shoreline or propwash. Lucky I had the Internet to back me up on this tall tale
../Wayne C.
[ September 10, 2003, 12:46 AM: Message edited by: awwt ]
As did I when I first heard it. Or, that it was bent in the shape of a ufer, or such. It sounds like something you might run into when you are on a snipe hunt or out trying to find some shoreline or propwash. Lucky I had the Internet to back me up on this tall tale
../Wayne C.
[ September 10, 2003, 12:46 AM: Message edited by: awwt ]
big john
Senior Member
- Location
- Portland, ME
Re: UFER
Or maybe a couple of 3/4 nimrods?
We were once doing some work in a school and one of the helpers was really getting on the nerves of this mechanic. The last straw was when the helper started asking everyone how they got the long flourescent bulbs into that "U" shape to fit the 2x2 fixtures. The mechanic tells him: "We use a flourescent tube bender... Which I think I left somewhere in the building. Go see find it for me." This poor guy actually went around from class to class asking the teachers if they had seen a flourescent tube bender. He couldn't understand why all the students laughed and all the instructors gave him dirty looks. :roll:
Sometimes it scares me the type of folks I find doing this work.
-John
Or maybe a couple of 3/4 nimrods?
We were once doing some work in a school and one of the helpers was really getting on the nerves of this mechanic. The last straw was when the helper started asking everyone how they got the long flourescent bulbs into that "U" shape to fit the 2x2 fixtures. The mechanic tells him: "We use a flourescent tube bender... Which I think I left somewhere in the building. Go see find it for me." This poor guy actually went around from class to class asking the teachers if they had seen a flourescent tube bender. He couldn't understand why all the students laughed and all the instructors gave him dirty looks. :roll:
Sometimes it scares me the type of folks I find doing this work.
-John
jxofaltrds
Inspector Mike®
- Location
- Mike P. Columbus Ohio
- Occupation
- ESI, PI, RBO
Re: UFER
Nimrod
Read Gen. 10 VS 9 & 10.
Mike P.
Nimrod
Read Gen. 10 VS 9 & 10.
Mike P.
iceman2610
Member
Re: UFER
Now there is a term I hadn't heard in a whileOriginally posted by awwt:
As did I when I first heard it. Or, that it was bent in the shape of a ufer, or such. It sounds like something you might run into when you are on a snipe hunt or out trying to find some shoreline or propwash. Lucky I had the Internet to back me up on this tall tale
../Wayne C.
dcsva@aol.com
Senior Member
- Location
- Virginia
Re: UFER
thanks awwt, that helps alot
thanks awwt, that helps alot
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