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Posted: May 19, 2009 04:04 PM	Why Mason Not that I want to put an ignition barrier on roofing foam, but why is Roofing Foam treated differently than foam on the inside of a building? Does this mean that Silicone paint can be used as an ignition barrier or should I just be quiet and keep on foaming roofs? Just asking! Steve
mason Posted: May 19, 2009 04:47 PM	SPF roofing systems just like every other roofing system have to be tested in accordance with UL 790 and be rated either a class A, B or C roof covering. The testing is a burn test at an angle to simulate a slope and a burning brand is also added to make sure that flying embers would not catch the roof system on fire. The procedure tests both the foam and the coating and the procedure gives the foam a rating on both combustible and non-combustible surfaces. Many foam and coating systems are approved typically as class A on non-combusitble and class B or C on combustible. UL lists the ratings along with the type of foam & maxiumum thickness, type of coating and thickness, plus the slope allowed. Another test procedure used for code approval is the FM Class I roof coverings procedures. In that the foam is tested for resistance to fires from inside the building and outside the building plus resistance to hail and to wind. Other tests that may be required when using foam roofing in a fire resistive assembly. In those situations a rating would be required that tests the roof coverings for a 1 , 2 or 3 hour rating from a fire on the inside of the building.
mason Posted: May 19, 2009 04:55 PM	I guess to further answer your question, fires on a roof tend to disipate the heat into the air where in the attic the heat is more concentrated and can lead to flashover.
Posted: May 19, 2009 04:57 PM	Is interior spray foam insulation also tested in accordance with UL 790, or is there another test that is done for this purpose?
mason Posted: May 19, 2009 05:16 PM	They use a room corner test to determine if foam can be used with a non code disignated thermal or ignition barrier. UL 1715, NFPA 286, FM 4880, UB 26-3 and a few others. I think a few of the roof coatings may be good as an igntion barrier but I don't know any that have been tested.

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Comments

Posted: May 19, 2009 04:04 PM

Why Mason

Not that I want to put an ignition barrier on roofing foam, but why is Roofing Foam treated differently than foam on the inside of a building?

Does this mean that Silicone paint can be used as an ignition barrier or should I just be quiet and keep on foaming roofs?

Just asking!

Steve

mason

Posted: May 19, 2009 04:47 PM

SPF roofing systems just like every other roofing system have to be tested in accordance with UL 790 and be rated either a class A, B or C roof covering. The testing is a burn test at an angle to simulate a slope and a burning brand is also added to make sure that flying embers would not catch the roof system on fire.

The procedure tests both the foam and the coating and the procedure gives the foam a rating on both combustible and non-combustible surfaces. Many foam and coating systems are approved typically as class A on non-combusitble and class B or C on combustible. UL lists the ratings along with the type of foam & maxiumum thickness, type of coating and thickness, plus the slope allowed.

Another test procedure used for code approval is the FM Class I roof coverings procedures. In that the foam is tested for resistance to fires from inside the building and outside the building plus resistance to hail and to wind.

Other tests that may be required when using foam roofing in a fire resistive assembly. In those situations a rating would be required that tests the roof coverings for a 1 , 2 or 3 hour rating from a fire on the inside of the building.

mason

Posted: May 19, 2009 04:55 PM

I guess to further answer your question, fires on a roof tend to disipate the heat into the air where in the attic the heat is more concentrated and can lead to flashover.

Posted: May 19, 2009 04:57 PM

Is interior spray foam insulation also tested in accordance with UL 790, or is there another test that is done for this purpose?

mason

Posted: May 19, 2009 05:16 PM

They use a room corner test to determine if foam can be used with a non code disignated thermal or ignition barrier. UL 1715, NFPA 286, FM 4880, UB 26-3 and a few others.

I think a few of the roof coatings may be good as an igntion barrier but I don't know any that have been tested.

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