What is a 'bonding grid', why do I need it?

[Geosage]

And why is it quoted by my pool cement guy (along with the walls and patio etc.) and not the PB?

(I'm in Southern California (Inland Empire))

Thanks!

 

[bdavis466]

The bond grid is 12" o.c. spacing of reinforcement steel centered in the decking 3' from the pools edge that wraps around the perimeter of the pool. It's purpose is to help keep the different materials around the pool at the same electrical potential to avoid shocks and dissipate stray voltage.

 

[Geosage]

Interesting, is it a noticeable voltage? I wouldn't think there could be that much differential. Our pool is backed up to a planter (and perimeter wall) on the one whole side (away from the house) and then the cement patio will be on the side facing the house.

I think I've encountered the effect of this not being installed before, we once lived at a community with a pool and when touching the light in the deep end you could notice a tingling at the screws on the mount etc...

 

[bdavis466]

That is part of what the grid prevents but could have a much greater impact from leakage from utility companies and faulty electrical work.

This was a part of the decking contractors bid because they are typically the one that installs it. I wouldn't be shocked (no pun) if the PB didn't know what it was or what it's for.

 

[borjis]

Yep that's it.

if you search the forum for bonding there is loads of info.

 

[bdavis466]

The old code provision called for a bare copper #8 to encircle the perimeter 18-24" from the edge. Most areas now require 12x12 copper mesh when reinforcing bar is not used. You'll need to check with your building department because this is often a grey area for most jurisdictions.