Spray foam: Thermal barriers & Intumescent coatings

TheHubbardBus

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Anyone out there using spray foam adhering to building code recommendations for a 15-minute thermal barrier? I was unaware of this until last night's reading, but it sure seems to make sense. Can't see drywall as very practical in our bus build, but I'm strongly considering adding an 'intumescent coating' - basically special paint - to achieve the ends of a thermal barrier when we do foam. For reference:


https://www.sprayfoam.com/content/faq-for-building-code-officials-/55


https://www.painttoprotect.com/fire...oam-spf/dc315-performance-testing-for-canada/
 
Interesting reads. I got our walls and roof spray foamed. I also installed clear lenses on our flasher/warning lamps, with hopes to use them in the future when I get them wired back up.

What are folks opinions on spray foam directly surrounding the internal dome of the warming lamps? I assume they get pretty hot. Should I cut the foam out around the fixture?

Also I have never heard of the phrase “intumescent”. The paint option seams reasonable, I may go that route as well.
 
I'm looking into aerogel blanket as thermal barriers wherever I need a mechanical connection to the ribs of the body. Holds up well to compression and has the best known R-value
 
Anyone out there using spray foam adhering to building code recommendations for a 15-minute thermal barrier? I was unaware of this until last night's reading, but it sure seems to make sense. [/URL]

It's odd to think that there would be a need to insulate your insulation, but most likely (since the article also mentions ignition barriers) the thermal barrier in this case would be to protect the insulation for a short period of time from the high heat generated by a fire (so that it doesn't start burning and generating toxic gases).

In the case of a tiny bus, this isn't really important because you would already be crispy fried chicken by the time a thermal barrier would make any difference.
 
It's odd to think that there would be a need to insulate your insulation, but most likely (since the article also mentions ignition barriers) the thermal barrier in this case would be to protect the insulation for a short period of time from the high heat generated by a fire (so that it doesn't start burning and generating toxic gases).

In the case of a tiny bus, this isn't really important because you would already be crispy fried chicken by the time a thermal barrier would make any difference.

I understand what you're saying. And in the likely majority of situations where heat or direct exposure to spark or flames could cause the foam to catch, I imagine the situation may be as you describe. But I can also envision other circumstances where an otherwise controllable fire, or spot heat source, could ignite and/or cause the foam to gas off, turning something slow & controllable into something fast and not in a quick hurry. This is conjecture - I admit having a limited understanding of foam technology or the variables associated with it - but to my way of thinking that's all the more reason to consider adhering to code standards.

If nothing else, it could help make the job less hazardous for fire fighting peeps forced to deal with it, and/or others in the vicinity of your really bad day.
 
I understand what you're saying. And in the likely majority of situations where heat or direct exposure to spark or flames could cause the foam to catch, I imagine the situation may be as you describe. But I can also envision other circumstances where an otherwise controllable fire, or spot heat source, could ignite and/or cause the foam to gas off, turning something slow & controllable into something fast and not in a quick hurry. This is conjecture - I admit having a limited understanding of foam technology or the variables associated with it - but to my way of thinking that's all the more reason to consider adhering to code standards.

If nothing else, it could help make the job less hazardous for fire fighting peeps forced to deal with it, and/or others in the vicinity of your really bad day.

I'm certainly not going to fault someone for adhering to code standards - unless it's the Comics Code Authority. That stuff was bullcrap.
 

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