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Icynene Spray Foam Insulation

skipharper

REGISTERED
Joined
Dec 23, 2009
Messages
242
Location
Louisa County, Va.
Is there a requirement in the 2009 IRC that states when using this product on your rafters and underside of the plywood that you protect it with a fire resistant material?
 
R316.4 Thermal barrier. Unless otherwise allowed in Section R316.5 or Section R316.6, foam plastic shall be separated from the interior of a building by an approved thermal barrier of minimum 1/2 inch (12.7 mm) gypsum wallboard or an approved finish material equivalent to a thermal barrier material that will limit the average temperature rise of the unexposed surface to no more than 250°F (139°C) after 15 minutes of fire exposure complying with the ASTM E 119 or UL 263 standard time temperature curve. The thermal barrier shall be installed in such a manner that it will remain in place for 15 minutes based on NFPA 286 with the acceptance criteria of Section R302.9.4, FM 4880, UL 1040 or UL 1715.



R316.5.3 Attics. The thermal barrier specified in Section R316.4 is not required where all of the following apply:

1. Attic access is required by Section R807.1.

2. The space is entered only for purposes of repairs or maintenance.3. The foam plastic insulation is protected against ignition using one of the following ignition barrier materials:3.1. 11/2 -inch-thick (38 mm) mineral fiber insulation;3.2. 1/4 -inch-thick (6.4 mm) wood structural panels;3.3. 3/8 -inch (9.5 mm) particleboard;3.4. 1/4 -inch (6.4 mm) hardboard;3.5. 3/8 -inch (9.5 mm) gypsum board; or3.6. Corrosion-resistant steel having a base metal thickness of 0.016 inch (0.406 mm). The above ignition barrier is not required where the foam plastic insulation has been tested in accordance with Section R316.6.
 
A gypsum board ceiling qualifies as a thermal barrier. Keep all mechanical equipment out of the attic space and you should be good.

Our policy is #2 is for repairs and maintenance on the building not mechanical equipment
 
I write in my remarks that the attic space can not be used for any purpose other than the servicing of utilities and the conditions of the space (like entry). I usually wouldn't allow the ceiling to be used as the thermal/ignition barrier if the attic is serviced by anything other than a 22x30 scuttle hole and there is any other allowance for storage.
 
If it has a flame spread of less than 25 and smoke developed less than 450, it is suitable for exposure even in an institutional occupancy. Icynene has products which meet this.
 
Skip the one thing the Icynene sales reps fail to read aroun here (I won't say on porpise) is the ESR report for thier own product.

Thermal and vapor barriers are mentioned in it quite often, note the exceptions in attic for "if accessed for mechanical access ONLY"

if there is a hatch and the attic qualifies as "Attic Storage" I see that as for other than mechanical access only especially if they produce the "NOTE FROM MOM"

that tells me they would never use it for storage...

see this one http://www.icynene.com/sites/default/files/downloads/ESR-1826Report_0.pdf

or this one http://www.icc-es.org/reports/pdf_files/ICC-ES/ESR-2715.pdf

and check for others as the product lines expand so do the stories....
 
Skip,

We just had their rep in last week to give us a training session. I can get you his contact info if you want it. They do have a paint on product for the closed cell that meets the ignition and smoke development requirements allowing it to be left exposed in attics and crawl spaces. They do recommend protecting it from termites in the crawl. The untreated foam is white and the foam that has been treated with the paint on product is creamy colored almost tan.

I found it interesting that you could apply the product directly to the underside of the roof sheathing without ventilation even with the open cell. I think that topic has been batted around here a few times. The wave of the future I am afraid.
 
Just had 4 hour training on spray foam this morning. That depends......Is it considered storage or hvac equipment access? Check ES reports on the foam manufacturer. Does it need a thermal barrier or an ignition barrier? Which energy code are you under?
 
One thing to remember with the foam on the underside of the roof. Some foams have a maximum thickness and that does not meet some energy code requirements for attic insulation r-value.
 
If it has a pull down stair or better, I see it as storage and it needs a thermal barrier. If it is a scuttle hole that requires bring a ladder, then it either needs ignition barrier or not depending on the/any equipment up there. Since a light is required , I do consider that a source of ignition.
 
Daddy-0- said:
Skip, We just had their rep in last week to give us a training session. I can get you his contact info if you want it. They do have a paint on product for the closed cell that meets the ignition and smoke development requirements allowing it to be left exposed in attics and crawl spaces. They do recommend protecting it from termites in the crawl. The untreated foam is white and the foam that has been treated with the paint on product is creamy colored almost tan. I found it interesting that you could apply the product directly to the underside of the roof sheathing without ventilation even with the open cell. I think that topic has been batted around here a few times. The wave of the future I am afraid.
Most sprayed foams meet the flame spread and smoke developed requirements. That's not the issue which requires the protection (as I mistakenly believed earlier). The issue which requires the protective board is described in the link I posted below.

tl;dr = although self extinguishing by standard tests, sprayed foams as applied are so efficient as insulation that they reflect heat back into the fire and cause such high temperatures that they burn...and so does everything else.
 
Imagine the heat reflecting capability of that reflective foil-faced board going in the hot climates...
 
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