Equipotential bonding for pools

Tonyhuynh916

Member
Location
Sacramento
Occupation
Rad Tech
Hi,

I am a homeowner and hired a terrible pool contractor. He built my pool without the proper inspections and now the county inspectors want me to prove that the pool is equipotentially bonded. We can clearly see the copper at the pool equipment pad and we can trace it around the perimeter of the pool. The concrete has already been poured and we can’t see the 4 bonding points around the pool. Is there anyway you can prove that the pool is equipotentially bonded together without breaking the concrete?
 

letgomywago

Senior Member
Location
Washington state and Oregon coast
Occupation
residential electrician
There is at great costs the option to do ground penetrating radar. The other option could be using a few rotohammered holes to gain access to the rebar and then demonstrate continuity between other pool bonds and the rest of the rebar.

Something you'll want to consider is the possibility that it isn't done correct and doing this may demonstrate that. If they skipped permits and inspections they probably skipped other things.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
Mike Holt had a video on this, but I can't locate it now.

One of the things he did was to take a reading from the service grounding electrode to a remote electrode. Remote being defined as outside the influence of any other grounding electrode or bonding metal in the earth. This electrode can just be a couple of feet of any conductive metal. |

There will always be a small voltage between the service grounding electrode and the remote electrode. This voltage will also appear on all of the bonded parts of the pool if the bonding was done in accordance to the requirements of the NEC.

Next you would measure the voltage from all of the conductive parts of the pool, including the water, to the remote electrode.
Ideally, since the voltage between the service grounding electrode and the remote one is changing with the load conditions on the electrical system, you would use two meters. One meter connected from the service grounding electrode to the remote electrode and the second one connected from the remote electrode and moved between all of the bonded parts of the pool. Even a concrete deck should show this voltage, but you will need to wet the concrete to get a good reading.
Seeing the same voltage on both meters indicates that the tested parts of the pool are bonded as required by the code.

Note, that this does not verify that the correct size of conductor was used, or the correct type of connections were used.
 

augie47

Moderator
Staff member
Location
Tennessee
Occupation
State Electrical Inspector (Retired)
Unfortunately this happens too often. I would suggest you contact some local reputable electrical contractors and see who has prior experience with this problem. They likely know what the County (Inspector) will accept.
I have seen some who only expect continuity checks between metallic enclosures and some who require the bond grid to be exposed.
 

Mystic Pools

Senior Member
Location
Park Ridge, NJ
Occupation
Swimming Pool Contractor
The fact the bond wire can be traced around the pool perimeter does not demonstrate it is in fact connected to the rebar or any of the 4 tails

If you have any pics during construction, it may be helpful.

Ultimately the concrete will have to be torn up to reveal the 4 tails, if they exist, and then proven that they are connected to the structure. I think the inspector will want to see them.

I agree with letgomywago that there's good chance the PB skipped other things. I've seen plenty of that.

Not sure of the width of your patio. Perhaps a solution is to saw cut and remove the concrete 2' back from the edge of the pool's perimeter, find the tails and perhaps the main bond wire, resolve the connections and replace the torn-up section with brick pavers.

Find an electrician in your area that is experienced with swimming pools to make the corrections for compliance.
 

Tonyhuynh916

Member
Location
Sacramento
Occupation
Rad Tech
The fact the bond wire can be traced around the pool perimeter does not demonstrate it is in fact connected to the rebar or any of the 4 tails

If you have any pics during construction, it may be helpful.

Ultimately the concrete will have to be torn up to reveal the 4 tails, if they exist, and then proven that they are connected to the structure. I think the inspector will want to see them.

I agree with letgomywago that there's good chance the PB skipped other things. I've seen plenty of that.

Not sure of the width of your patio. Perhaps a solution is to saw cut and remove the concrete 2' back from the edge of the pool's perimeter, find the tails and perhaps the main bond wire, resolve the connections and replace the torn-up section with brick pavers.

Find an electrician in your area that is experienced with swimming pools to make the corrections for compliance.
Seems like the only way is to tear up the concrete and check for the bonding points . And it’s not done right, we would have to redo it.
 

Jpflex

Electrician big leagues
Location
Victorville
Occupation
Electrician commercial and residential
Hi,

I am a homeowner and hired a terrible pool contractor. He built my pool without the proper inspections and now the county inspectors want me to prove that the pool is equipotentially bonded. We can clearly see the copper at the pool equipment pad and we can trace it around the perimeter of the pool. The concrete has already been poured and we can’t see the 4 bonding points around the pool. Is there anyway you can prove that the pool is equipotentially bonded together without breaking the concrete?
Does anyone on this post know why standard rebar and wire ties would not provide equipotential bonding? Do contractors normally take pictures or have an inspector sign off before pouring concrete?
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
Does anyone on this post know why standard rebar and wire ties would not provide equipotential bonding? Do contractors normally take pictures or have an inspector sign off before pouring concrete?
The rebar and standard ties do provide part of the equipotential bonding but the bonding conductor must be connected to the rebar as part of tying everything together.
In some areas, the AHJ permits pictures, and in other areas the AHJ must go to the site to inspect before the concrete is poured.
 

Strathead

Senior Member
Location
Ocala, Florida, USA
Occupation
Electrician/Estimator/Project Manager/Superintendent
Seems like the only way is to tear up the concrete and check for the bonding points . And it’s not done right, we would have to redo it.
It was just brushed over, but ground penetrating radar may be a better option. It is probably around $2000 to $2500 (probably double that is California, regretfully). That would really only be worth it IF the work was done. Was the rebar inspected? I am wondering if it was properly tied. I want to point out that the bonding is done for safety. If the rebar wasn't properly tied, then all the bonding in the world won't do any good. PS, I lived in Fairfield/Vacaville for 25 years.
 

Tonyhuynh916

Member
Location
Sacramento
Occupation
Rad Tech
It was just brushed over, but ground penetrating radar may be a better option. It is probably around $2000 to $2500 (probably double that is California, regretfully). That would really only be worth it IF the work was done. Was the rebar inspected? I am wondering if it was properly tied. I want to point out that the bonding is done for safety. If the rebar wasn't properly tied, then all the bonding in the world won't do any good. PS, I lived in Fairfield/Vacaville for 25 years.
I had a gpr scan done but that was only for the placement of the rebar to make sure it was good structurally. The ppl can’t do a gpr scan to make sure the copper was tied correctly. He was able to trace the copper around the perimeter of the pool but that was it.
 

Mystic Pools

Senior Member
Location
Park Ridge, NJ
Occupation
Swimming Pool Contractor
More than likely the perimeter bonding was done as the tracing confirms, but all bets are off because the inspector never had the chance to see if before the pour.
 

Tonyhuynh916

Member
Location
Sacramento
Occupation
Rad Tech
More than likely the perimeter bonding was done as the tracing confirms, but all bets are off because the inspector never had the chance to see if before the pour.
I also have a picture of one of the bonding points behind the spa but the inspector said it’s not good enough. He wants to see all four. We may have to rip out all of the decking and redo it.
 

Mystic Pools

Senior Member
Location
Park Ridge, NJ
Occupation
Swimming Pool Contractor
I also have a picture of one of the bonding points behind the spa but the inspector said it’s not good enough. He wants to see all four. We may have to rip out all of the decking and redo it.
Too bad you're having such trouble.
Yes, I figured he would want to physically see them.

I will suggest that once you tear up concrete, hire an electrician experienced with swimming pools. He may be able to or may know someone that can perform a bonding certification. This is something required for public/commercial pools, but I think it's a good idea for your pool to verify it is in fact bonded.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
What about some type of equipment that can take pictures thru the concrete. I don't know if one even exists. I read ground penetrating radar

BTW, why can't you get the pool builder to eat this
 
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