Closed cell spray foam

Knuckle Dragger

Knuckle Dragger

Master Electrician Electrical Contractor 01752
Location
Marlborough, Massachusetts USA
Occupation
Electrical Contractor
Have any of you had your nmb, speaker wires, thermostat lines or low voltage UCL lines damaged by closed cell spray foam insulation?

I had some of my LV lines to the under cabinet LED tape light damaged closed cell spray foam.(I rung out them out to find the damaged lines).
It happened on the second round when they insulted the basement, ceiling and sills. The lights worked fine for months before they spayed.

Are you guys using or familiar with any high temperature rated low voltage wires?
 
I'll take "wire was already damaged" for $1000, Alex.

I've never heard nor seen foam doing that. Not doing electrical work as a main course anymore; however, I do get roped into wiring barns and new out buildings for all kinds of rural friends. A bunch of them are ran with NM, speaker wire, but no LV. No one wants to spend the money to EMT them in like I did mine. I've never seen a wire buried in foam get damaged thus. Open cell or closed cell. Been around both. It does go on pretty hot but cool pretty fast as well.
 
Is it possible that the solvent in the spray foam could attack some types of conductor insulation material?
 
ggunn said:
Is it possible that the solvent in the spray foam could attack some types of conductor insulation material?
Click to expand...
It is more likely that if the damage was from the spray foam installation, it was heat. You have to keep the layers relatively shallow, because the base/catylyst reaction is very exothermic (heat generating).
 
Was the insulation applied to the walls? We have had LV wires cut by the insulators when they shave the foam flush with the studs.

I'm seldom around when they insulate but have seen them use a special 3' sawzall blade to cut the insulation. We had one job where the blade plunged into the ceiling area and cut one of our Homeworks keypad wires. Of course this doesn't show up until the end of the job when programing the system.

I have never had wires damaged directly by the spray foam.

Anytime spray foam is being used, you need to secure wires very well. Staple every 12" - 18". The foam will push the wires out of the wall/ceilings. If the insulators don't damage them trimming the insulation the drywall guys will.
 
I'll try to keep the story line short.
All LV wires were roughed in along with all the other wires. The walls were closed cell sprayed foamed. Trimmed out all devices after the blue board, plaster, trim paint etc. Everything worked great for three months at least.The basement was closed cell spray foam insulated after three months at the building inspectors request (please don't get hung up on that ;))
Sometime after that the homeowner noticed some of the
 
It is a chemical mix, and seems the install is highly dependent on correct outside temperature and humidity? I could see if one of those things is off you could get material that isn't reacting properly and might degrade other materials, and it seems like there were articles about these failed installs.
vtdigger.org

'I wanted to cry': Devastating risks of spray foam insulation hidden from Vermont homeowners - VTDigger

When asked how a homeowner could assess whether they’re hiring a high-quality insulation installer, Brent Ehrlich, a products and materials specialist at BuildingGreen, said, “I don't really have a good answer to that.”
vtdigger.org vtdigger.org

Even if its perfect install in construction with organic materials like wood seems you would want to vent in at least one direction and spray foam insulation would prevent moisture from escaping?
And after you spend $$$ making a home "air-tight" you have to spend more on expensive high maintenance fans and equipment to bring that air right back in.
Its probably great for metal or masonry buildings though.
 
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