Hot Tub

[Dennis Alwon]

Hey another question is, would I be crossing boundaries to ask an electrical inspector in the area this question? Do they get bent out of shape about stuff like this? Do you guys ask your electrical inspectors questions?

I think it is very appropriate to ask the inspector. Some do not feel it is there job to answer your question but I believe they are not the majority. Ask him/her, they may tell you it is not necessary but the NEC still requires it.

The 2008 NEC spells it out a bit differently

680.26 Equipotential Bonding.
(A) Performance. The equipotential bonding required by this section shall be installed to reduce voltage gradients in the pool area.

(B) Bonded Parts. The parts specified in 680.26(B)(1) through (B)(7) shall be bonded together using solid copper conductors, insulated covered, or bare, not smaller than 8 AWG or with rigid metal conduit of brass or other identified corrosion-resistant metal. Connections to bonded parts shall be made in accordance with 250.8. An 8 AWG or larger solid copper bonding conductor provided to reduce voltage gradients in the pool area shall not be required to be extended or attached to remote panelboards, service equipment, or electrodes.
(1) Conductive Pool Shells. Bonding to conductive pool shells shall be provided as specified in 680.26(B)(1)(a) or (B)(1)(b). Poured 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. Vinyl liners and fiberglass composite shells shall be considered to be nonconductive materials.
(a) Structural Reinforcing Steel. Unencapsulated structural reinforcing steel shall be bonded together by steel tie wires or the equivalent. Where structural reinforcing steel is encapsulated in a nonconductive compound, a copper conductor grid shall be installed in accordance with 680.26(B)(1)(b).
(b) Copper Conductor Grid. A copper conductor grid shall be provided and shall comply with (b)(1) through (b)(4).
(1) Be constructed of minimum 8 AWG bare solid copper conductors bonded to each other at all points of crossing
(2) Conform to the contour of the pool and the pool deck
(3) Be arranged in a 300-mm (12-in.) by 300-mm (12-in.) network of conductors in a uniformly spaced perpendicular grid pattern with a tolerance of 100 mm (4 in.)
(4) Be secured within or under the pool no more than 150 mm (6 in.) from the outer contour of the pool shell
(2) Perimeter Surfaces. The perimeter surface shall extend for 1 m (3 ft) horizontally beyond the inside walls of the pool and shall include unpaved surfaces as well as poured concrete and other types of paving. Bonding to perimeter surfaces shall be provided as specified in 680.26(B)(2)(a) or (2)(b) and shall be attached to the pool reinforcing steel or copper conductor grid at a minimum of four (4) points uniformly spaced around the perimeter of the pool. For nonconductive pool shells, bonding at four points shall not be required.
(a) Structural Reinforcing Steel. Structural reinforcing steel shall be bonded in accordance with 680.26(B)(1)(a).
(b) Alternate Means. Where structural reinforcing steel is not available or is encapsulated in a nonconductive compound, a copper conductor(s) shall be utilized where the following requirements are met:
(1) At least one minimum 8 AWG bare solid copper conductor shall be provided.
(2) The conductors shall follow the contour of the perimeter surface.
(3) Only listed splices shall be permitted.
(4) The required conductor shall be 450 to 600 mm (18 to 24 in.) from the inside walls of the pool.
(5) The required conductor shall be secured within or under the perimeter surface 100 mm to 150 mm (4 in. to 6 in.) below the subgrade.

 

[Poolside]

Reinforcing steel in perimeter surface

Reinforcing steel in perimeter surface

I have a few pool builder contractors that I work with. To get the permimeter surfaces bonded as required by the 2005 NEC, they have the concrete contractor tie a rebar grid together that is connected to the pool steel via #8 bonding wires. They never did this in the past. When they reinforced the deck in the past it was with wire mesh not rebar. The NEC doesn't specify the size of the steel, so I would think the mesh would be acceptable, too. Is this true or am I missing something in the reading?

I assume they are tying the rebar, because this is what they know to do because of the pool shell is done in like fashion.

BTW- In this part of CA (Southern), the bonding is more than likely done by the plumbing crew, not the electrical crews. They just do as they are told without question or regard to NEC requirements.


Thanks,
Greg

 

[M. D.]

poolside , they changed the wording in the 08 to allow the AHJ decide if mesh can be used for the EG

17-92 Log #950 of the 2007 ROC:


Panel Statement: The revised text more clearly presents the requirements and meets the intent of the submitter. The panel has removed the word ?(rebar)? from 680.26(B)(1)a to clarify that welded wire mesh can be included in the term ?structural reinforcing steel? where acceptable to the authority having jurisdiction.
Number Eligible to Vote: 11
Ballot Results: Affirmative: 10
Ballot Not Returned: 1 Gill, C

NY high,
I posted this in this thread I think it is accurate based on 05..perhaps there will be more discussion on it's merit
hot tub bond - Mike Holt's Forum

If the concrete in the O.P. does not extend beyond the footprint of the hot tub and it constructed of plastic/fiberglass/or other non conductive material, there is no need for a grid under it. If the concrete does extend out ,.... grid required under that portion up to 3' or a conrete saw is required to cut it off :smile:

Quote:
Reference: 680.26 TIA 05-2 (NFPA 70) (SC 05-7-15)/Log No. 821) Pursuant to Section 5 of the NFPA Regulations Governing Committee Projects, the National Fire Protection Association has issued the following Tentative Interim Amendment to NFPA 70, National Electrical Code?, 2005 edition. The TIA was processed by the National Electrical Code? Committee, and was issued by the Standards Council on July 29, 2005, with an effective date of August 18, 2005. A Tentative Interim Amendment is tentative because it has not been processed through the entire standards-making procedures. It is interim because it is effective only between editions of the standard. A TIA automatically becomes a proposal of the proponent for the next edition of the standard; as such, it then is subject to all of the procedures of the standards-making process.

1. Revise 680.26 (C) & 680.26 (C)(1) as follows: (C) Equipotential Bonding Grid. The parts specified in 680.26(B) shall be connected to an equipotential bonding grid with a solid copper conductor, insulated, covered, or bare, not smaller than 8 AWG or rigid metal conduit of brass or other identified corrosion-resistant metal conduit. Connection shall be made by exothermic welding or by listed pressure connectors or clamps that are labeled as being suitable for the purpose and are of stainless steel, brass, copper, or copper alloy. The equipotential bonding grid shall conform to the contours of the pool and shall extend within or under paved walking surfaces for 1 m (3 ft) horizontally beyond the inside walls of the pool and shall be permitted to be any of the following: Exception: The equipotential bonding grid shall not be required to be installed under the bottom of or vertically along the walls of vinyl lined polymer wall, fiberglass composite, or other pools constructed of nonconductive materials. Any metal parts of the pool, including metal structural supports, shall be bonded in accordance with 680.26(B). For the purposes of this section, poured concrete, pneumatically applied (sprayed) concrete, and concrete block, with painted or plastered coatings, shall be considered conductive material. (1) Structural Reinforcing Steel. The structural reinforcing steel of a concrete pool or deck where the reinforcing rods are bonded together by the usual steel tie wires or the equivalent. Where deck reinforcing steel is not an integral part of the pool, the deck reinforcing steel shall be bonded to other parts of the bonding grid using a minimum 8 AWG solid copper conductor. Connection shall be per 680.26(D).

Copyright ? 2005 All Rights Reserved NATIONAL FIRE PROTECTION ASSOCIATION

 

[Poolside]

Thanks M.D. for the information.

- Greg

 

[Pierre C Belarge]

I understand your point. I will read a little more under this subject. As for the receptacle within 25 feet of the Hot tub for servicing, is that necessary or is that just for heating/a.c. equipment. Thanks again guys, this is a great site!

As for Pierre, thanks for the info, I'm actually not sure what year the code for this installation falls under in this area. You'd think the latest code right? HAHA...But that's the world of NEC.

As per my earlier post:
P.S. Residential pools (& spas) in NYS are following the Residential Building Code, Chapter 41 and also referencing the 2002 NEC.

In NYS, you will not be required to follow the requirements of the '05 or '08 NEC. The bonding grid so many are refering to is not a requirement for ECs in NYS.

 

[M. D.]

As per my earlier post:
P.S. Residential pools (& spas) in NYS are following the Residential Building Code, Chapter 41 and also referencing the 2002 NEC.

In NYS, you will not be required to follow the requirements of the '05 or '08 NEC. The bonding grid so many are refering to is not a requirement for ECs in NYS.

Well ,..he posted in the NEC section I figure he wants to meet the requirements of a more current document ,..2002 ??,..the dark ages code wise....:smile: