# concrete pad bonding



## RIVETER (Sep 26, 2009)

*Bonding a concrete pad*



nolabama said:


> Would drilling something like a concrete sleeve anchor in a pad and bolting a lug to it be legal for pad bonding?
> 
> sleeve anchor is pictured here http://www.confast.com/products/concrete-sleeve-anchor.aspx


Is this a serious question? I ask this because I sometimes get ripped for someone not understanding my humor, or my not understanding theirs. I mean no harm so I will answer...seriously. If I were to pour a concrete pad knowing that I may want to ground it, I would insert iron mesh and bond all sections and then drive a ground rod.I am not the authority but that would be the minimum that I would do.


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## BuzzKill (Oct 27, 2008)

nolabama said:


> Would drilling something like a concrete sleeve anchor in a pad and bolting a lug to it be legal for pad bonding?
> 
> sleeve anchor is pictured here http://www.confast.com/products/concrete-sleeve-anchor.aspx


 negative...you have to get to the rebar in the pad.


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## nolabama (Oct 3, 2007)

RIVETER said:


> Is this a serious question? I ask this because I sometimes get ripped for someone not understanding my humor, or my not understanding theirs. I mean no harm so I will answer...seriously. If I were to pour a concrete pad knowing that I may want to ground it, I would insert iron mesh and bond all sections and then drive a ground rod.I am not the authority but that would be the minimum that I would do.


Yes this is a serious question. No this is not for a new pour. If you need to bond something -like the hot tub in the other thread- to an existing concrete pad would this anchor be legal? Its just bonding the EGC not the GEC is it not?


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## william1978 (Sep 21, 2008)

Just take a angle grinder and cut a grove with a diamond tip blade and then push the #8 down in the grove.


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## RIVETER (Sep 26, 2009)

*Grounding a concrete pad*



nolabama said:


> Yes this is a serious question. No this is not for a new pour. If you need to bond something -like the hot tub in the other thread- to an existing concrete pad would this anchor be legal? Its just bonding the EGC not the GEC is it not?


I am not the foremost guru, that may be PeterD, but I would want lightning protection as best as I could...that rings of grounding to earth. AS far as the hot tub electrical, it is a branch circuit, I believe, and the code spells it out.


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## BuzzKill (Oct 27, 2008)

william1978 said:


> Just take a angle grinder and cut a grove with a diamond tip blade and then push the #8 down in the grove.


 Gotta hit the steel in the pad in order to be sufficient, and then it needs to be bonded well.


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## RIVETER (Sep 26, 2009)

*Bonding a concrete pad*



BuzzKill said:


> Gotta hit the steel in the pad in order to be sufficient, and then it needs to be bonded well.


Bonding and grounding are different even though they are at the same potential. Grounding has to do with EARTH grounding, via, an electrode, of some sort. Bonding has to do with whatever it takes to achieve THAT same potential.


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## BuzzKill (Oct 27, 2008)

RIVETER said:


> Bonding and grounding are different even though they are at the same potential. Grounding has to do with EARTH grounding, via, an electrode, of some sort. Bonding has to do with whatever it takes to achieve THAT same potential.


 yeah whatever, you have to bond to the steel in order to have sufficient ground(ing).


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## RIVETER (Sep 26, 2009)

*Bonding/grounding*



BuzzKill said:


> yeah whatever, you have to bond to the steel in order to have sufficient ground(ing).


You are correct...If you have building steel columns, they have to be considered as grounding electrodes.


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## leland (Dec 28, 2007)

william1978 said:


> Just take a angle grinder and cut a grove with a diamond tip blade and then push the #8 down in the grove.



Then patch it in of course. Then seal it to match the existing. Done.

Thats a good answer William, and easy


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## BuzzKill (Oct 27, 2008)

leland said:


> Then patch it in of course. Then seal it to match the existing. Done.
> 
> Thats a good answer William, and easy


 Sounds hack-y.


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## RIVETER (Sep 26, 2009)

*Grounding/bonding*



BuzzKill said:


> Sounds hack-y.


It is. There is so much mis information or misunderstanding about grounding/bonding, it could be a subject unto itself.


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## BuzzKill (Oct 27, 2008)

william1978 said:


> Just take a angle grinder and cut a grove with a diamond tip blade and then push the #8 down in the grove.


 Sounds great! And then when there is a ground fault on the equipment, whoops! it won't clear and someone gets bit.


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## qckrun (May 18, 2009)

RIVETER said:


> It is. There is so much mis information or misunderstanding about grounding/bonding, it could be a subject unto itself.


 Exactly why do you think there were so many changes to section 250 in the 08 code lol.


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## RIVETER (Sep 26, 2009)

*Grounding/bonding*



qckrun said:


> Exactly why do you think there were so many changes to section 250 in the 08 code lol.


I've not seen the changes...I just kind of know.


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## nolabama (Oct 3, 2007)

Bonding structural steel to the GEC for lighting protection is not what I am talking about. I can see, however, where you would want to bond to the steel in the concrete. I don't see how a wire put in a groove cut in the concrete is much better that what I have suggested, and might take longer too. So for an existing concrete pad that needs to be bonded the only correct way is to break concrete and bond to the rebar?


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## waco (Dec 10, 2007)

No. Obtaining an equipotential grid goes much farther than that and yes, inserting a wire into a cut in the slab looks as good as the real thing, but it doesn't get it done.

Portable pools/tubs don't require equipotential grids, but some sort of non-conductive surround wouldn't be a bad idea. I wouldn't get in a hot tub if I had to, but I'd sure rather step into one from an insulated rather than a non-insulated surface. I'm thinking about those weird effects of damaged underground service conductors and bare feet on a wet concrete floor and bare hands in the water.


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## nolabama (Oct 3, 2007)

waco said:


> No. Obtaining an equipotential grid goes much farther than that and yes, inserting a wire into a cut in the slab looks as good as the real thing, but it doesn't get it done.
> 
> Portable pools/tubs don't require equipotential grids, but some sort of non-conductive surround wouldn't be a bad idea. I wouldn't get in a hot tub if I had to, but I'd sure rather step into one from an insulated rather than a non-insulated surface. I'm thinking about those weird effects of damaged underground service conductors and bare feet on a wet concrete floor and bare hands in the water.


If they dont require equipotential grids then what is the point?


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## william1978 (Sep 21, 2008)

BuzzKill said:


> Sounds great! And then when there is a ground fault on the equipment, whoops! it won't clear and someone gets bit.


 I talking about 680.26. Just what kind of faults are you talking about?


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## nitro71 (Sep 17, 2009)

I would say the only way to bond a existing slab is to chisel out some concrete and hope there is rebar in it. Since you didn't install it and can't test it the inspector would have to waive some rules. Using the hot tub as an example, the inspectors in my area do not require a equipotential grid for self contained/portable tubs.


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## BuzzKill (Oct 27, 2008)

william1978 said:


> I talking about 680.26. Just what kind of faults are you talking about?


 I don't think the OP is talking about anything having to do with pools or hot tubs; the sleeve anchor he mentions needs to be bonded somehow to an EGC to clear any ground fault, or dead short.


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## william1978 (Sep 21, 2008)

BuzzKill said:


> I don't think the OP is talking about anything having to do with pools or hot tubs; the sleeve anchor he mentions needs to be bonded somehow to an EGC to clear any ground fault, or dead short.


 I just don't understand why we would be wanting to ground a concrete slab.


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## william1978 (Sep 21, 2008)

nolabama said:


> Would drilling something like a concrete sleeve anchor in a pad and bolting a lug to it be legal for pad bonding?
> 
> sleeve anchor is pictured here http://www.confast.com/products/concrete-sleeve-anchor.aspx


Why are you needing to do this?


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## Magnettica (Jan 23, 2007)

nolabama said:


> Would drilling something like a concrete sleeve anchor in a pad and bolting a lug to it be legal for pad bonding?
> 
> sleeve anchor is pictured here http://www.confast.com/products/concrete-sleeve-anchor.aspx




The Ufer connection should have been made prior to the concrete pour as required by 250.52 (A)(3). 

If the concrete pad is existing don't worry about it.


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## leland (Dec 28, 2007)

I'm still with you William. BONDING- NOT GROUNDING.

That simple.


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## leland (Dec 28, 2007)

nolabama said:


> Would drilling something like a concrete sleeve anchor in a pad and bolting a lug to it be legal for pad bonding?
> 
> sleeve anchor is pictured here http://www.confast.com/products/concrete-sleeve-anchor.aspx



Just to get back to the original post


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## nolabama (Oct 3, 2007)

BuzzKill said:


> I don't think the OP is talking about anything having to do with pools or hot tubs; the sleeve anchor he mentions needs to be bonded somehow to an EGC to clear any ground fault, or dead short.


 I am talking about bonding a hot tub to the existing concrete pad. I was wondering if one could use the anchor that I put in the original post would suffice. I don't have an 08 code book yet, as we are graded on 05 currently, so I am not up on the changes.

In another post a guy said something about Bonding the hot tub to the concrete pad. This sounds to me like the frame of the hot tub is to be Bonded to the EGC and the concrete slab, not Bonding the concrete slab to the GEC(which would Earth/Ground the slab). I don't know if that is the case or not. If all your doing is bonding the frame to the pad I cant see why that little anchor is any worse than the suggestion that William put forth.


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