Swimming Pool Equipotential Bonding

[Spaulding]

I have Bonded and wired about 125 Swimming pools but now I have a rather unique project. The pool is inground, formed with uncoated rebar and the rebar does not extend beond the coping edge of the pool. There are also NO ladders, no wet niche housings, railings or any other metal in contact with the water.

Question 1 Does the reinforced gunite or concrete act as suitable contact to bond the water? I have seen the water bonding equipment that goes in the skimmer but if I do not need it I would rather not because I am sure the pool builder would have a problem with me drilling a hole in his skimmer.

Question 2 I have located a #8 bonding mesh from GREAVES in Conneticuit
which comes as a kit to be laid horizontally around the pool which would later be covered by Pavers. I believe that this mesh has to connect at four seperate points to the rebar circumfrence of the pool. Since it is copper #8 cad welded at 12" intervals can this be bonded to a piece of #8 with copper burndys and then down to the grid using a listed lug type device for rebar?

 

[raider1]

I have Bonded and wired about 125 Swimming pools but now I have a rather unique project. The pool is inground, formed with uncoated rebar and the rebar does not extend beond the coping edge of the pool. There are also NO ladders, no wet niche housings, railings or any other metal in contact with the water.

Question 1 Does the reinforced gunite or concrete act as suitable contact to bond the water? I have seen the water bonding equipment that goes in the skimmer but if I do not need it I would rather not because I am sure the pool builder would have a problem with me drilling a hole in his skimmer.

I would not consider the concrete pool lining to bond the pool water. You will need another device to comply with 680.26(C)

Question 2 I have located a #8 bonding mesh from GREAVES in Conneticuit
which comes as a kit to be laid horizontally around the pool which would later be covered by Pavers. I believe that this mesh has to connect at four seperate points to the rebar circumfrence of the pool. Since it is copper #8 cad welded at 12" intervals can this be bonded to a piece of #8 with copper burndys and then down to the grid using a listed lug type device for rebar?

That sounds compliant to me.

Chris

 

[augie47]

I hope I don't "step in it" here..I hate pools...
My OPINION is that the GREAVES grid is for bonding the pool conductive shell when the lining steel isn't available or encapuslated and it (the Grid) must conform to the pool shell.
The perimeter equiopotential bond is esatblished by structural steel (bar or mesh) or a #8 installed per 680.26(B)(2)(b).
The GREAVES grid is not necessary for perimter bonding and if it were only used for the perimeter it would not satisfy bonding of the pool shell.

Am I wrong, Chris ?

 

[Cavie]

Yes, the concrete steal must be bonded to the expotential ground grid or ring. In Florida, we used a #8 bare ground ring around the pool within 18" of the waters edge. The Graves Grid is very expencive and unsessessary. I have not seen it used here. The 4 point connection is made with direct bury split bolts on the ring and J-junior clamps on the rebar.

 

[Spaulding]

Pool bonding

Pool bonding

I completly understand the concept and if I can run a single #8 solid around the perimeter I will however, if you look at different intepitations some call for the #8 in 12" cross patterns on all sides of the pool out 3' from the edge to meet code. There are no rebars extending horizontally after they come up from the side walls of the forming shell. Other intepitations also say that the concrete or GUNITE is part of the equipitenial bonding grid and being in contact with the pool water would be ok. I believe the big difference here is if the pool were vinyl lined or fibrglass then one would have to bond the water by putting in a greater than 9 sq inch plate in the scupper or put in a metallic fitting at the pump that would meet the requirement. I would not like to do either if not really nessesary. Maybe the 12"x 12" mesh is designed for pools without any rebar.

 

[raider1]

I hope I don't "step in it" here..I hate pools...
My OPINION is that the GREAVES grid is for bonding the pool conductive shell when the lining steel isn't available or encapuslated and it (the Grid) must conform to the pool shell.

Yes, the GREAVES grid can be used for that purpose.

The perimeter equiopotential bond is esatblished by structural steel (bar or mesh) or a #8 installed per 680.26(B)(2)(b).
The GREAVES grid is not necessary for perimter bonding and if it were only used for the perimeter it would not satisfy bonding of the pool shell.

Am I wrong, Chris ?

Under the 2005 NEC the 3' perimeter paved walking surface and pool shell had to be bonded by the reinforcing steel or by an alternate means that had #8 copper wires in a 12 x 12 pattern that were bonded at each intersecting corner.

So therefore if you choose to have the GREAVES grid under just the paved walking surface in the 2008 NEC and you bond the grid to 4 corners of the pool shell grid you would be compliant with 680.26(B)(2).

Chris