Ufer, Sub-panel, Pool, ...a little help?

[BMacky]

I am working on a new construction project where the structure is a "pool pavillion" located next to an in-progress pool installation. When I showed up to look at the job, the GC noted he had left a Ufer (stranded #4) in the stud bay where the sub-panel will be installed in a utility room.

Here's some basic known data:

- The structure will be fed from a new main located at streetside (rural area in N. California) with an underground feed to the sub-panel located in the structure's utility room. The underground work will be sub'd out, but assume it to be a typical 400A meter/main with distribution.

- The pool equipment will be fed from the structure's sub-panel

- The structure has no bedrooms or kitchen, etc. Only a bathroom, sitting area, bar and utility/laundry room. I add this as it may not be considered a dwelling unit, unless the definition of such covers this type of structure.

Here's some assumed data:

- the ufer is tied into rebar in the structure foundation only, not the pool or pool deck rebar.

Here are the questions:

- What sort of grounding scenario would be totally code-compliant here?

I assume (haven't researched this yet, and generally go over it with pool installers) that the pool deck and associated pool rebar grid will have to be bonded to the sub-panel. Please consider this as well.

- The ufer (stranded #4) left in the stud bay where the sub-panel shall be installed appears to be too short to reach the panel if it is to be installed at a proper height. Any suggestions on how to work with that scenario? I have not crawled under the sub-floor yet, so am not sure if there is additional length to pull or not.

Thanks for any/all code references that apply!

 

[elohr46]

I am working on a new construction project where the structure is a "pool pavillion" located next to an in-progress pool installation. When I showed up to look at the job, the GC noted he had left a Ufer (stranded #4) in the stud bay where the sub-panel will be installed in a utility room.

Here's some basic known data:

- The structure will be fed from a new main located at streetside (rural area in N. California) with an underground feed to the sub-panel located in the structure's utility room. The underground work will be sub'd out, but assume it to be a typical 400A meter/main with distribution.

- The pool equipment will be fed from the structure's sub-panel

- The structure has no bedrooms or kitchen, etc. Only a bathroom, sitting area, bar and utility/laundry room. I add this as it may not be considered a dwelling unit, unless the definition of such covers this type of structure.

Here's some assumed data:

- the ufer is tied into rebar in the structure foundation only, not the pool or pool deck rebar.

Here are the questions:

- What sort of grounding scenario would be totally code-compliant here?

I assume (haven't researched this yet, and generally go over it with pool installers) that the pool deck and associated pool rebar grid will have to be bonded to the sub-panel. Please consider this as well.

- The ufer (stranded #4) left in the stud bay where the sub-panel shall be installed appears to be too short to reach the panel if it is to be installed at a proper height. Any suggestions on how to work with that scenario? I have not crawled under the sub-floor yet, so am not sure if there is additional length to pull or not.

Thanks for any/all code references that apply!

The pool forming shell rebar and the deck rebar (equipotental bonding grid) do not get bonded to the pool equipment panel. They get bonded to the pool equipment (pumps, heaters, etc.) and all metal parts associated within the pool (ladders, lighting, etc.) and all metal parts within 5' of the inside wall of pool (fence, diving board, etc.).

 

[nakulak]

680 (2005)

 

[tryinghard]

- The ufer (stranded #4) left in the stud bay where the sub-panel shall be installed appears to be too short to reach the panel if it is to be installed at a proper height. Any suggestions on how to work with that scenario?

If the electrode has been installed as per 250-52(A)(3) and the #4 cu is 20' near the bottom of the foundation it is the electrode therefore the GEC can connect to it (accessible above foundation) and route to its destination.

If the #4 cu is NOT 20' near the bottom of the foundation (or is unknown) it can only be assumed non-compliant as an electrode and the GEC begins at its connection to the rebar (250-68(A) Exception No. 1) and has to remain continuous in length to it's destination. In this case it can only be lengthened as per 250-64(C)(1). Other wise install a new electrode.

 

[Dennis Alwon]

I would like to clarify that if there is 20 foot of rebar at least 1/2" in diameter in the footing that is tied to the rebar in the foundation then you do not need 20 foot of #4 copper.

It is my understanding that if yu are bonded to the rebar via some approved clamp then the copper only needs to be as long as necessary to reach the panel.

For the other section read 680.26-- it basically states that all pool equipment that is metal must be bonded together not tied back to the panel.

 

[tryinghard]

It is my understanding that if yu are bonded to the rebar via some approved clamp then the copper only needs to be as long as necessary to reach the panel.

I believe this is BMacky's problem the GEC is existing and the footing is poured. This is a good example of reality because panel locations move and the GEC begins at the electrode, in this case it sounds like it's in the foundation and inaccessible.

If so he'll have to install a different electrode and abandon the inaccessible one, or lengthen the GEC as per 250-64(C)(1)