Spray Foam Insulation in Electrical Panel

If you were to seal the service entrance cable from the interior wouldn’t you think it would eventually fill up with water from condensation and potential moisture entry from the exterior? any sealing should take place from the exterior with approved materials.


The NEC only requires that raceways are sealed. The idea is not to provide a seal that is waterproof. The goal is to keep different temperature air from meeting and condensing. Duct seal is what we use.


I absolutely agree. As I mentioned earlier, I think it should be done at the point of entry to the home, not the panel board. I do not think spray foam or any other foreign substance should be there.


Thanks everybody. Its a manufactured home. We all know they do whatever they want lol

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Is there a local amendment that states a minimum height on a panel? Asking since the NEC does not have a minimum height.

A panel mounted at a higher level could still be within a childs reach. A panel would offer less of a hazard than a receptacle to a child.

The NEC is a permissive document. If something is not stated as not allowed it is by default allowed.

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He stated it’s a part of the CEC. Additionally, he stated that the panel is not to be installed in a hazardous location, such as to where it would be more susceptable to damage, etc…

Why does the height matter in a home inspection? It’s not a code compliant inspection and I see no safety or function concerns.

I see no overheating concern.

I see a strong electrical fire concern. “Great stuff” burns “Great”, like a solid gasoline.
A minor electrical fire in that box could spread to the rest of the house because of the foam.

Foams are just not that good at resisting fire, even the orange colored fire block foam gets roaring.

I would call out foreign material in the box in general, and
combustible foam specifically, then recommend the foam be completely removed and replaced with a proper Intumescent Firestop Caulk.

metacaulk 1000 Fire Intumescent

This is a case where doing nothing would have been better than what they did.


Even though I defended having a tiny bit of foam spill into the panel in the OP’s picture. This one from today went too far, lol.


:rofl: :rofl: :rofl: :rofl:


If they are dumb enough to do it they probably didnt know it would expand.

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The foam was sprayed into the wall cavity behind the panel. They probably never thought about infiltration through the screw holes.

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I was thinking that, too, Jim.

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Above comments by Robert and others are correct, duct seal is the way to go here, not expanding spray foam. Too many red flags for use inside a panel can.

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