Need help understanding electrical bonding and my pool

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kilkenny

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Nov 19, 2015
15
Santa rosa ca
Specifically in relation to the pool coping alone. Coping isn't metal. The material that will be up against the coping is dirt and grass. Does the coping require bonding? Would love an explanation considering the coping is brick and attached to the bond beam with cement. :confused:
 
The type of coping you are describing doesn't require bonding because it is not metal.
Everything made of metal requires bonding.

If you read somewhere that coping needs to be bonded, then that was probably referring to a vinyl pool which the word "coping" is sometimes used to refer to an aluminum piece around the perimeter of the pool from which the liner hangs.

kilkenny said:
Specifically in relation to the pool coping alone. Coping isn't metal. The material that will be up against the coping is dirt and grass. Does the coping require bonding? Would love an explanation considering the coping is brick and attached to the bond beam with cement. :confused:
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This pool is 40 years old. The old coping has been removed. What is left is the bond beam. There are some parts of the pool where rebar comes out of the top and is bent over toward where the old concrete patio was. That patio is being replaced with dirt and grass (maybe artificial grass). If I was doing a concrete or paver setup I think I might need to bond it, but I'm not. New coping should just be able to be installed on top of the old bond beam.

Just trying to figure this out before I go to the city.
 
To be clear, I'm not putting any decking down. It will be grass (maybe artificial). The only hard substance is the actual coping which would be attached to the bond beam. That article states only concrete or paver decking would be conductive.

FYI: I am talking to the city but I want to avoid any permitting requirement for this.
 
First, I'm not an electrician, I don't play one on TV and I didn't stay at a Holiday Inn Express last night. I'm a guy on the internet with a little bit of knowledge - which can be scary at times.

So, if my understanding is correct the grass would be the "deck" and the equipotential bonding grid would be under the grass, just like it would be under a paver deck. The idea is that the pool, water, and anything that can be reached while you are in the pool is maintained at the same potential to ground. In the construction of a new pool you would attach bonding wires (solid conductor not smaller than 8 AWG) to the rebar in the shell at four distinct points around the perimeter of the pool, and that same wire is then attached to the deck grid and any other metal objects around the pool.

A great resource for pool electric is ARTICLE 680—SWIMMING POOLS, SPAS, HOT TUBS, FOUNTAINS, AND SIMILAR INSTALLATIONS by Mike Holt Enterprises. You are looking for 680.26 in this document, but it may help with other things you are doing.

Understand that bonding (not to be confused with normal grounding) is fairly new and few electricians have any clue what it is. There was apparently a lot of dissent when this was proposed and then added to the National Electrical Code. With a little googling you can find some of the electrical forums and you will find some "spirited" discussion.....
 
A photo or two of the pool/deck area might help us better understand your situation.
Please consider adding your pools info to your signature as outlined here in "Getting Started" - > Pool School - Getting Started
For a lot of questions it's so much easier if we know the equipment.
 

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kilkenny said:
This is similar to how it would look. Everything I've read states you only need that bonding if the material is conductive, which grass is not.
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680.26 says:
(2) Perimeter Surfaces. Equipotential bonding must extend 3 ft horizontally beyond the inside walls of a pool including unpaved, paved, and poured concrete surfaces.
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I do believe grass would fit the definition of an unpaved surface.

Plus, I don't know if I would agree that grass is a non-conductive surface, especially after it gets a little water splashed on it.

When it comes down to it it is your pool to do with as you please.
 
I leave the electrical stuff up to others (oh gweagan where art thou??) but I'll say this for the design - definitely NOT live grass!!! Use a high quality artificial turf. Think about it like this - you have to cut, water and fertilize grass. As the old Sesame Street song goes - "two of those things are not like the other / two of things just don't belong / which two of those things are not like the other / which two of those things do not belong?"

Answer - you don't want grass clippings or fertilizer anywhere near your pool.
 
kilkenny said:
Not when the city is involved. :)
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If you are going to involve them, call and ask. I have found through the years that municipal/county inspectors are really not the "enemy" that many make them out to be. When it comes down to it they are looking out for the safety of your family. Additionally, if you do involve them they will most probably require you to have a licensed electrician handle these parts of the remodel.

Who knows, they may say bonding is not required. There are lots (millions maybe) or pools out there with no equipotential bonding, mine included (I think). These pools were built before the need was understood and the requirement was added to the NEC. Are these pools unsafe? Probably not. Are pools with an equipotential bond safer? I say yes.
 
This is a somewhat controversial area. It never hurts to call the local inspector and ask. Give your neighbor with a pool's address if they ask for one.

I would not call that a unpaved surface that requires a bonding grid. I don't think a Sacramento County inspector would call for one. But they would call what you are doing a remodel and want you to install some sort of bonding in the pool.

It could not hurt to put a metal grid under the new coping and attach it to some kind of a water bond. That way when you step out of the pool onto the coping you don't inadvertently become a conductor. Small risk, but the injury can be serious.
 
The bond grid is required in my area whether you have decking or not. As was previously stated, the equipotential bond grid is put in place to keep all nearby surfaces and the pool at the same electrical potential. The bond grid can also help mitigate stray voltage gradients that may come into play.

Your building department should be consulted on what they require.
 
Mr Kilkenny.... I was a licensed electrican (years back) but, although some rules have changed, volts & amps still do the same stuff they always did. Anyway, if you have no metal anywhere near the pool & pool area, your risk is very minimal. (BTW, I added a plastic handrail which is rated as totally non-conductive). Ceramic tile is essentially also non-conductive (think of ceramic insulators used by the power company). For one last piece of insurance & for absolute piece of mind, simply cut the power to the pool when you are using the pool, if that would make you more comfortable. Cool looking pool!
 
RainyDay said:
Mr Kilkenny.... I was a licensed electrican (years back) but, although some rules have changed, volts & amps still do the same stuff they always did. Anyway, if you have no metal anywhere near the pool & pool area, your risk is very minimal. (BTW, I added a plastic handrail which is rated as totally non-conductive). Ceramic tile is essentially also non-conductive (think of ceramic insulators used by the power company). For one last piece of insurance & for absolute piece of mind, simply cut the power to the pool when you are using the pool, if that would make you more comfortable. Cool looking pool!
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The problem with this is that the bonding requirement is not there for pool supplied electric, say the underwater light which is protected by a GFCI.

It was created to protect against stray voltage, differences in potential form one thing to another. As it has been explained to me it mainly deals with stuff like nearby lightning strikes, issues with the neutral on the power company transformer and the like. It is not grounding, it is bonding. Bonding every conductive item within reach of the pool (including the pool water) so that there is no way there can be a difference in potential between two objects you can be in contact a with at the same time.

Here is the 2008 NEC Handbook commentary on that question:
It is important to understand the difference between the terms bonding and grounding as they apply to Article 680. As defined in Article 100, bonding is ``the permanent joining of metallic parts to form an electrically conductive path that ensures electrical continuity and the capacity to conduct safely any current likely to be imposed.'' As described in 680.26(A), the function of equipotential bonding differs from the function of bonding to meet the requirements of Article 250 in that providing a path for ground fault current is not the function of the equipotential bonding grid and associated bonding conductors.
Creating an electrically safe environment in and around permanently installed swimming pools requires the installation of a bonding system with the sole function of establishing equal electrical potential (voltage) in the vicinity of the swimming pool. A person who is immersed in a pool or who is dripping wet, has a large amount of exposed skin, and is lying or walking on a concrete deck is extremely susceptible to any differences in electrical potential that may be present in the pool area.
The primary purpose of bonding in and around swimming pools is to ensure that voltage gradients in the pool area are not present. The fine print note explains that the 8 AWG conductor's only function is equipotential bonding to eliminate the voltage gradient in the pool area.
The reason for connecting metal parts (ladders, handrails, water-circulating equipment, forming shells, diving boards, etc.) to a common bonding grid [pool reinforcing steel, pool metal wall, or an alternative bonding grid as described in 680.26(C)(3)] is to ensure that all such metal parts are at the same electrical potential. The grid reduces possible injurious or disabling shock hazards created by stray currents in the ground or piping connected to the swimming pool. Stray currents can also exist in nonmetallic piping because of the low resistivity of chlorinated water.
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Mike Holt explains bonding here:YouTube - 2014 NEC - Pool Equipotential Bonding [680.26]. At 07:24 he discusses the utility loosing it's neutral.

Herfe Mike discusses stray voltage: Mike Holt Stray Voltage Video
 

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