ECN Forum Forums General Topics of the Trade General Discussion Area Spray foam filled electrical outlets

There is a study out there that came up over RX in foamed penetrations.(334.80)

http://gfretwell.com/electrical/NEMA%20Romex%20in%20foam%20study.pdf

Tesla, your concern is not completely unfounded.

NEMA, however, has issued a letter on the matter. After various tests, etc., it was determined that foam insulation posed no particular cause for concern. The jacket was NOT harmed by the foam chemicals, and there was NOT excessive heating on properly sized wires.

I agree that expanding foams are very combustible.

I would like to ad this link
http://www.safetyauthority.ca/files...%20Polyurethane%20Spray%20Form%20Ins.pdf

She asked for it, he did it. Had she asked to have all the plumbing vent stacks sealed with foam, he would have done that too.

If he refused, she would have found someone else to do it. The customer is always right.

It seems accessibility would also be an issue,which would be in direct NEC violation. You'd have to pry out an outlet and the wire for service and/or inspection. I don't like it.

As for peope letting drywall mud and paint into panels, almost every interior panel I've opened that was installed prior to 1980 has an absurd amount of crap in it. Apparently they had not heard of masking off anything that the buyer would not normally see before purchasing the house. This usually includes te busses as well!

I imagine he also insulated all of the switch boxes as well?
The guy probably thought the orange fire stop expanding spray foam that they sell at HD and Lowe's was just perfect for the task at hand. I'd hate to be the guy who has to clean out all those boxes... that stuff dries really hard, almost like structural spray foam... and what about dimmer switches, etc., when they start overheating.

You never know these days though. This insulation guy might end up being considered a pioneer and nominated for the next Nobel Peace Prize.

I am sure the foam issue is not an issue in the walls. the OP was foam in the in the box itself which is not mentioned in the NEMA study.

I've seen instructions on the cans of spray foam saying not to use it inside electrical boxes. So it's definitely not "listed for the purpose"...

arent they supposed to label the cans "fill around electrical boxes and penetrations"?

Accessibility. If this foam gets hard, the conductors are no longer accessible.