Pool Water Bonding

[Christoph]

I have a pool company that (after I pointed at the thing) claims that their sacrificial zinc anode provides the water bonding for their Pool in accordance with 680.26(C).

Naturally after receiving the info on the anode from the contractor I got on the phone with the manufacturer and they say that this anode is indeed in contact with the water 18 square inches. However they understand that this product is made to corrode away and they of course do not advertise this as a pool water bond for that reason. A very interesting thing that this gentleman pointed out is that if there is a heater "that has an awful lot of metal in it". To sleep at night accepting that I would want to see some documentation on the pool heater that shows me that the heating coils are properly bonded and that the manufacturer is comfortable and in agreement with that circumstances.

How do you inspectors or installers handle this? No ladder on this job and no wet-niche metallic luminaire.

 

[suemarkp]

That should be part of the NRTL listing process. Even if the heating elements shorted to some metal in the heater that is in contact with the water, I'm not so sure water is conductive enough to really be a problem in a heater that is a distance away from the pool and plumbed with PVC pipes.

 

[Christoph]

That should be part of the NRTL listing process. Even if the heating elements shorted to some metal in the heater that is in contact with the water, I'm not so sure water is conductive enough to really be a problem in a heater that is a distance away from the pool and plumbed with PVC pipes.

I hope we are on the same page here. With the EQ Plane I am looking for something to touch the water at all times. I thought of listing converns as well, but then again a metallic pool ladder is not listed grounding and bonding equipment and neither is any part of this required to be as far as I can tell.

 

[Mystic Pools]

I posed the same question about the heater coils to an inspector when this code was first introduced, didn't fly.
Sacrificial anode will eventually corrode.

Perma-Cast PB2008 Water Bonding fitting.
The pool plumber will have to provide a 1" female NPT fitting.

This is the only type I use. They make water bonding for skimmer bodies, but they won't be very accessible if they need replacement.

 

[Greentagger]

The water is considered bonded if pool shell was rebar and sprayed with gunnite.

 

[Dennis Alwon]

The water is considered bonded if pool shell was rebar and sprayed with gunnite.

Where is that in the NEC. I have never seen it,

 

[Dennis Alwon]

It makes sense since gunnite is conductive.

 

[don_resqcapt19]

Where is that in the NEC. I have never seen it,

(C) Pool Water.
Where none of the bonded parts as specified in 680.26(B)(1) through (B)(7) are in direct connection with the pool water, the pool water shall be in direct contact with an approved corrosion-resistant conductive surface that exposes not less than 5800 mm2 (9 in.2) of surface area to the pool water at all times. The conductive surface shall be located where it is not exposed to physical damage or dislodgement during usual pool activities, and it shall be bonded in accordance with 680.26(B).

680.26(B)(1) is the conductive pool shell. Concrete and gunnite are conductive and are in contact with the pool water, and as long as the reinforcing is bonded as required, you don't have to do anything additional to comply with the pool water bonding requirement.

 

[Mystic Pools]

680.26(B)(1) is the conductive pool shell. Concrete and gunnite are conductive and are in contact with the pool water, and as long as the reinforcing is bonded as required, you don't have to do anything additional to comply with the pool water bonding requirement.

That in 2023?

 

[don_resqcapt19]

That in 2023?

The basic rule has been the same since the pool water bonding requirement was added in the 2014 code. The wording was a bit more generic in the 2014 through the 2020 codes. The 2023 added the specific reference to the parts required to be bonded by the rules in 680.26(B)(1) through (B)(7). The intent of the change was only for clarification and was not a technical change. The bonded, conductive pool shell has been permitted to bond the water ever since the rule to require the water to be bonded was added to the code.

(C) Pool Water.
Where none of the bonded parts are in direct connection with the pool water, the pool water shall be in direct contact with an approved corrosion-resistant conductive surface that exposes not less than 5800 mm2 (9 in.2) of surface area to the pool water at all times. ...

 

[Mystic Pools]

Ok. Inspectors are still requiring water bonding for my pools which are gunite. Last one in Monmouth County NJ a few months ago.

I look at this from the structural standpoint and how it's stated that pool water is in contact with pool water. If the bonded rebar is contact with the pool water, then is a problem with the structure and failure of the reinforcement is imminent. Add in the pool chemicals to move things along.

I did a build on the Hudson River 2 years ago and every 12 hours the tide rises with briny/brackish water and will make contact with the pool shell. (2) sump pumps keep it bay but tick tock on that rebar lasting from exposure to that environment.

There are products that make a concrete structure, including pools, waterproof. I use one such product. It's a cement-based material that's rolled on, sprayed on or troweled to the inside of the pool. There are rubber membranes used in my industry also.
Other contactors shoot pools in the wet method as opposed to the dry method of gunite. The term Shotcrete covers both wet and dry application according to the ACI, but gunite in my trade covers dry application with water mixed at the nozzle.
Some "wet shot" contractors will add waterproofing agents in the concrete trucks sometimes at the site to the entire concrete mix. Xypex is one predominant product.

So, when I apply the waterproofing material I prefer, no longer allowing pool water (according to code verbiage) to migrate through the shell to the rebar, is the structure now non-conductive? Therefore, requiring water bonding?

Some vinyl pool contractors do not use steel or polymer walls but pour reinforced concrete walls. Where do they fit in?

 

[don_resqcapt19]

Ok. Inspectors are still requiring water bonding for my pools which are gunite. Last one in Monmouth County NJ a few months ago.

I look at this from the structural standpoint and how it's stated that pool water is in contact with pool water. If the bonded rebar is contact with the pool water, then is a problem with the structure and failure of the reinforcement is imminent. Add in the pool chemicals to move things along.

I did a build on the Hudson River 2 years ago and every 12 hours the tide rises with briny/brackish water and will make contact with the pool shell. (2) sump pumps keep it bay but tick tock on that rebar lasting from exposure to that environment.

There are products that make a concrete structure, including pools, waterproof. I use one such product. It's a cement-based material that's rolled on, sprayed on or troweled to the inside of the pool. There are rubber membranes used in my industry also.
Other contactors shoot pools in the wet method as opposed to the dry method of gunite. The term Shotcrete covers both wet and dry application according to the ACI, but gunite in my trade covers dry application with water mixed at the nozzle.
Some "wet shot" contractors will add waterproofing agents in the concrete trucks sometimes at the site to the entire concrete mix. Xypex is one predominant product.

So, when I apply the waterproofing material I prefer, no longer allowing pool water (according to code verbiage) to migrate through the shell to the rebar, is the structure now non-conductive? Therefore, requiring water bonding?

Some vinyl pool contractors do not use steel or polymer walls but pour reinforced concrete walls. Where do they fit in?

The code does not directly address a nonconductive coating on the surface of the pool shell. It probably should, but I don't recall any recent Pubic Inputs to address this.
The code only says:

680.26(B)(1) ....Cast-in-place concrete, pneumatically applied or sprayed concrete, and concrete block with painted or plastered coatings shall all be considered conductive materials due to water permeability and porosity. Reconstructed pool shells shall also meet the requirements of this section. Vinyl liners and fiberglass composite shells shall be considered to be nonconductive materials and not subject to these requirements.

 

[GoldDigger]

I look at this from the structural standpoint and how it's stated that pool water is in contact with pool water. If the bonded rebar is contact with the pool water, then is a problem with the structure and failure of the reinforcement is imminent. Add in the pool chemicals to move things along.

The wording in the code of "In direct connection" seems deliberately chosen instead of "in direct contact." That suggests to me that what is required is an electrical connection from a bonded part to the water, where they have chosen not to go into detail about the mechanism, required maximum resistance, etc.
I agree that direct physical contact between some of the bonded parts and the pool water would be a really bad idea.