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Jeffrey Maine Posted: Apr 14, 2010 11:41 AM	IB Hello Mason I have a steel building that we sprayed. The building has open truss. The 14' walls are covered with plywood. The the codes person is stating that an IB will not be sufficent. Any ideas?
mason Posted: Apr 14, 2010 12:25 PM	I need a little more detail. Where is the foam installed on the walls and the underside of the roof deck? Is there a drop ceiling below the roof deck? Is the plywood the interior surface over the foam on the walls?
Jeffrey Maine Posted: Apr 14, 2010 12:32 PM	The foam is on the inside walls sprayed on steel exterior sheathing, covered with plywood. Yes the foam is sprayed on the underside of roof deck with no drop ceilings.
mason Posted: Apr 14, 2010 02:46 PM	The foam would require a thermal barrier on the underside of the roof deck. The foam under the plywood is a little trickier. I doubt if the plywood over foam would pass a thermal barrier test unless the plywood was pretty thick. Also, I doubt if the plywood and SPF combination would pass one of the ICC code approved room corner tests such as UL 1715 or UBC 263 or NPFA 286. But During the 70s, a lot of fire testing was performed on rooms with foam plastics (including SPF) with a large variety of coverings including wood. It sounds like the code official is looking for this kind of fire test over foam to allow the plywood over foam without a thermal barrier. Check out the various plywood manufacturers for fire testing that might relate to the application. Or ask your supplier if they have tested plywood and SPF in that type of configuration.
Jeffrey Maine Posted: Apr 14, 2010 03:31 PM	Sorry I should have been more clear. They only have a problem with the IB that we want to apply to the foem on the under side of the roof deck. The walls with the plywood passes. We wanted to use the Blaze Loc IB.
Posted: Apr 15, 2010 04:16 AM	foam requires a thermal barrier covering when exposed to habitable space... blazeloc ib is an ignition barrier,,suitable for attics and crawls,,,but not exposed to habitabal space... you need to look at flame seal tb,,a code approved intumesent coating for thermal barrier covering over foam... (how thick is the plywood covering?)...
Jeffrey Maine Posted: Apr 15, 2010 06:58 AM	Thanks for the help Mason. I have some technical data being sent to the codes.
jimcoler I have over 10 years of experience specifying and installing open and closed cell spray foam. I've sold my business but I'm still selling for the new owners and consulting on large and custom specific jobs. I've expanded my knowledge into t Posted: Apr 15, 2010 11:39 AM	Theres another company out there called Paint-to-Protect which has a product called DC-315. This would suffice as your Ignition Barrier and Thermal Barrier with just a coat of paint. It's available through us or another local distributer. Please let us know if you'd like us to quote it for you.

Author

Comments

Jeffrey Maine

Posted: Apr 14, 2010 11:41 AM

Hello Mason
I have a steel building that we sprayed. The building has open truss. The 14' walls are covered with plywood. The the codes person is stating that an IB will not be sufficent. Any ideas?

mason

Posted: Apr 14, 2010 12:25 PM

I need a little more detail.

Where is the foam installed on the walls and the underside of the roof deck?

Is there a drop ceiling below the roof deck?

Is the plywood the interior surface over the foam on the walls?

Jeffrey Maine

Posted: Apr 14, 2010 12:32 PM

The foam is on the inside walls sprayed on steel exterior sheathing, covered with plywood.
Yes the foam is sprayed on the underside of roof deck with no drop ceilings.

mason

Posted: Apr 14, 2010 02:46 PM

The foam would require a thermal barrier on the underside of the roof deck. The foam under the plywood is a little trickier.

I doubt if the plywood over foam would pass a thermal barrier test unless the plywood was pretty thick. Also, I doubt if the plywood and SPF combination would pass one of the ICC code approved room corner tests such as UL 1715 or UBC 263 or NPFA 286.

But

During the 70s, a lot of fire testing was performed on rooms with foam plastics (including SPF) with a large variety of coverings including wood.

It sounds like the code official is looking for this kind of fire test over foam to allow the plywood over foam without a thermal barrier.

Check out the various plywood manufacturers for fire testing that might relate to the application.

Or ask your supplier if they have tested plywood and SPF in that type of configuration.

Jeffrey Maine

Posted: Apr 14, 2010 03:31 PM

Sorry I should have been more clear. They only have a problem with the IB that we want to apply to the foem on the under side of the roof deck. The walls with the plywood passes. We wanted to use the Blaze Loc IB.

Posted: Apr 15, 2010 04:16 AM

foam requires a thermal barrier covering when exposed to habitable space...
blazeloc ib is an ignition barrier,,suitable for attics and crawls,,,but not exposed to habitabal space...
you need to look at flame seal tb,,a code approved intumesent coating for thermal barrier covering over foam...
(how thick is the plywood covering?)...

Jeffrey Maine

Posted: Apr 15, 2010 06:58 AM

Thanks for the help Mason. I have some technical data being sent to the codes.

jimcoler

I have over 10 years of experience specifying and installing open and closed cell spray foam. I've sold my business but I'm still selling for the new owners and consulting on large and custom specific jobs.

I've expanded my knowledge into t

Posted: Apr 15, 2010 11:39 AM

Theres another company out there called Paint-to-Protect which has a product called DC-315. This would suffice as your Ignition Barrier and Thermal Barrier with just a coat of paint.

It's available through us or another local distributer. Please let us know if you'd like us to quote it for you.

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