I am in the final stages of erecting a 30×40 metal building that will be my shop. (I decided to build the shop before starting on the house. That way when the house is done I will still have my dream shop.) I want to use spray foam insulation but I have been discovering that alll spray foams must be covered to meet code.(I am building in Colorado) Is there a spray on fireproofing that will meet the 15min.flame and smoke requirement and not eat the foam? (I am considering using Iycenene brand foam. I REALLY don’t want to sheet the underside of the roof.
Thanks,
Doug
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Using drywall is usually the quickest, easiest, cheapest method - but you are not without any other options.
Most any of the cementicious coverings that you see applied to steel beams will work. These coatings - often mis-identified as 'asbestos' - are of great enough thickness to provide the protection that you need. It is possible that you will need to have some sort of 'chicken wire' mesh to help support the coating.
Likewise, a stucco finish of enough thickness should work.
What is 'enough thickness?' Well, allowing for variations, etc ... I'd say to aim for 1" thick. If you have a UL design number, AND you have followed the specs, then a lesser thickness might be acceptable.
As for some sort of miracle paint, foil, or blanket ... forget it. It does not exist.
Intumescent paints like these http://www.contegointernational.com/ and http://www.firefree.com/ should work.
Thanks for the info. Depending on price the paint type products certainly seem to be an easier way to go.(I am doing most of the work my self so the idea of rocking the underside of the roof is not very appealing)
Doug
You're welcome, and welcome to Breaktime.
Both of those web sites are very misleading as to the fire ratings of their products. Contego, in particular, tries to baffle you with BS. I repeat myself: There is NO WAY a coat of paint can substitute for a substantially thick fire wall or barrier. Period. The UL/ANSI test to look for is ANSI 263. In this test, wall, ceiling, or floor sections are tested, as an entire assembly, by exposing them to a massive fore for a substantial period of time. Temperatures inside are controlled to follow a curve, and temperatures outside are monitored. As you might guess, the basic structure has a great impact upon the resistance of the assembly. For example, a block wall will perform differently than a stud wall. Products tested under this standard WILL state the "Design Number" that there were tested on. Instead, the cited products reference tests of surface burning characteristics .... NOT fire resistance. Don't be fooled by fancy words, such as "intumescent" or "ablative." Such products typically withstand exposures in seconds, not hours. Then they're gone. If you want to protect the space shuttle for the few seconds of re-entry, they work fine; but for a prolonged fire test they leave a lot to be desired.
Our local Demelac crew has a fireproof spray they can run over the foam especially for this purpose. I would check with the Icenene crew, they should have something like it. So far I've been able to use drywall so I don't know how much it would cost.
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