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chris mcintyre
03-01-2010, 05:14 PM
While the title of the thread may be a little deceiving :), I was curious if this is wrong or just a bad idea. This is a new construction house with a crawl space , the main panel is in the garage which is the reason for it being so low in the house.

Jerry Peck
03-01-2010, 05:22 PM
I was curious if this is wrong or just a bad idea.


It's wrong because it's a bad idea. :)

No insulation below the panel.

Exposed facing on the insulation below the tub.

No insulation in that wall where the panel is.

Panel in wall does not meet minimum 1/2" gypsum separation.

IF any water gets behind that wall the panel will rust out, and hopefully nothing worse.

IF that is a spa tub, where it the motor access?

ken horak
03-01-2010, 07:20 PM
Jerry your slipping ;) :eek:

No mention of that pvc male adaptor used as a connector on the ser cable or the concern over the possible damage to the ser cable due to its location ?

Jerry Peck
03-01-2010, 07:27 PM
Jerry your slipping ;) :eek:

No mention of that pvc male adaptor used as a connector on the ser cable

:eek: TOTALLY MISSED THAT!


or the concern over the possible damage to the ser cable due to its location ?

Considered that, then realized that is really no different than NM cable under a spa tub ... other than it being "service" entrance cable versus "branch" circuit cable.

I also noted, but forgot to write down, the missing sealant around the cables going down through that bottom plate - needed for fireblocking. I even looked at each of those cables going into those clamps and totally blew over that adapter for the service entrance ... I'll take 40 lashes with a wet noodle and go back to my corner. :o

Roger Frazee
03-01-2010, 09:53 PM
Why is it that I'm having a hard time seeing myself using that tub......;)

Vern Heiler
03-02-2010, 08:31 AM
It's wrong because it's a bad idea. :)

Panel in wall does not meet minimum 1/2" gypsum separation.

Jerry, curious about this observation. Would two sheets of metal, greater than 24ga. separated by 4" of air, qualify as fire separation? I see panels in garage separation walls all the time but have never given this a thought.

Not picking, honest question.

Jerry Peck
03-02-2010, 05:41 PM
Panel in wall does not meet minimum 1/2" gypsum separation.


Jerry, curious about this observation. Would two sheets of metal, greater than 24ga. separated by 4" of air, qualify as fire separation? I see panels in garage separation walls all the time but have never given this a thought.

Not picking, honest question.

That metal is going to heat up when there is a fire, and, if you understand the ratings for firestopping there is a T-rating and that T-rating is the time it takes the penetrating item (metal, of course, plastic does not transfer heat the way metal does) to heat up on the non-fire side of the wall/ceiling/floor.

The 1/2" gypsum, which is not fire-rated, provides a temperature/time separation, i.e., slows the travel time for temperature from one surface to another, which is why it is only required on the garage side.

Put a fire on that metal panel and it is going to transfer that heat right through the wall almost immediately, defeating the reason for requiring 1/2" gypsum board as separation.

What if it was 1/2" thick plate steel - no fire is going through that sucker ... but the heat sure will.

Jerry Peck
03-02-2010, 06:17 PM
Jerry, I know that IPE lumber from Brazil is class A rated for flame spread. Would it be possible to panel a wall between a tub area and a possible fire source and achieve an adequate T-rating. IPE is much heavier than oak.


Only an engineering in that field could say so and sign and seal it - remember also that the panel will be against regular studs.

The better solution would be to make a 5-sided box to fit in the wall and the electrical panel to then be mounted in that 5-sided box - the 5-sided box takes the separation wall "around" the panel. Better yet - relocate the panel to either be surface mounted or to another wall location away from the separation wall as the 5-sided box will be destroyed trying to get all that wiring into that panel ... ;)