New Spa install: reccomendations?

[jjhoward]

A customer is about to pour a 4" concrete pad for his new outdoor spa. Should re-bar be installed to be used as a grounding grid?
If yes, any suggestions on where to leave the rebar sticking out (side, top, corner?) to attach the bonding wire?

Thank you for the input.

 

[bradleyelectric]

Re: New Spa install: reccomendations?

I'm not sure that you would need rebar, but if it is used I wouldn't leave any sticking out. I'd bond to it and leave a piece of copper sticking out in the area where the control panel will be so it can be both hidden and easy to install. You may need a bond inspection if it is done this way. Why don't you call the AHJ and ask him?

 

[infinity]

Re: New Spa install: reccomendations?

Also I would check to see what code version the jurisdiction is using. Here in NJ we're still under the 2002 NEC which does not contain the requirement for the equipotential bonding under spas. This is a new requirement for the 2005.

 

[jjhoward]

Re: New Spa install: reccomendations?

I will leave the inspector a vmail and hope he gets back to me before the cust pours the concrete. If this town is not using the 2005 yet we are OK to do nothing re: the rebar. How should the rebar be tied together if it is to be used as a grounding grid? For mechanical use different rebar pieces are wrapped with wire where they cross each other. Must they be clamped to make a grnd grid?

 

[infinity]

Re: New Spa install: reccomendations?

The standard tie wires that are used to tie the rebar together are fine. Or you could install something like this:

Look here for more info on this bonding grid:

http://www.electrical-contractor.net/Forum/Images/BondingGrid-5.jpg

 

[jjhoward]

Re: New Spa install: reccomendations?

Hi Infinity,
I don't have the 2005 code book yet, (ordered the CD + handbook today.) What type of requirements are there for a grid under a spa? Is there min awg, min length?