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Rob Granger Posted: Oct 09, 2007 12:23 PM	Residence on Stilts Mason, We have talked about crawl and attics needing an ignition barrier but I have a residence on stilts coming up where the owner wants the underside(to weather) of the floor sprayed but it will not be covered afterwards... Does it require an ignition barrier in this application. Thanks
mason Posted: Oct 09, 2007 01:10 PM	There is debate on the issue. Some say that if it is not a crawl space (ie no sides) and is not inhabited space that no thermal or ignition barrier is required. Others say the ignition barrier requirement is implied in this type of configuration. The codes do not address this application but in other exterior applications (such as roofing) the igntion and thermal barrier rules do not apply. But in the case of roofing applications, the codes require a class a, b or c roof covering rating for residential roofing in accordance with UL 790 or its equivalent. I am going to pose this question to ICC and post their answer when I receive it. (as a member I can ask their interpretation of code language.)
Rob Granger Posted: Oct 09, 2007 05:14 PM	Mason, Another questions arises in that although I am going to spray CC would you suggest an additional vapor barrier. I am in New York State and temps get to 15 degrees easily and at times zero degrees. Thanks
philip mullins Posted: Oct 09, 2007 08:15 PM	thats getting popular down here as well. with the new codes many homes are 10-15 feet in the air. the codes here say nothing on this matter iether. BUT, i would never leave the site without an ignition barrier. it wont be long before your customer is parking his grill under thier. along with his mower and cans of gas, his boat, etc... none of witch is a good idea with or without foam but, THEY DO IT EVERY TIME. CYA bud!
mason Posted: Oct 10, 2007 03:55 PM	I received an answer from ICC. Because it is outside of the inhabited area and is not an attic or crawl space it does not require a thermal barrier. However, as Troutkiller points out it is not a bad idea to coat it with an intumescent coating to act as an ignition barrier. In answer to your question about cold weather condensation, so long as you have a sufficient thickness of closed cell foam (2 inches or more), you should not have a problem with long term moisture problems.

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Comments

Rob Granger

Posted: Oct 09, 2007 12:23 PM

Residence on Stilts

Mason,
We have talked about crawl and attics needing an ignition barrier but I have a residence on stilts coming up where the owner wants the underside(to weather) of the floor sprayed but it will not be covered afterwards... Does it require an ignition barrier in this application.

Thanks

mason

Posted: Oct 09, 2007 01:10 PM

There is debate on the issue. Some say that if it is not a crawl space (ie no sides) and is not inhabited space that no thermal or ignition barrier is required. Others say the ignition barrier requirement is implied in this type of configuration.

The codes do not address this application but in other exterior applications (such as roofing) the igntion and thermal barrier rules do not apply. But in the case of roofing applications, the codes require a class a, b or c roof covering rating for residential roofing in accordance with UL 790 or its equivalent.

I am going to pose this question to ICC and post their answer when I receive it. (as a member I can ask their interpretation of code language.)

Rob Granger

Posted: Oct 09, 2007 05:14 PM

Mason,
Another questions arises in that although I am going to spray CC would you suggest an additional vapor barrier. I am in New York State and temps get to 15 degrees easily and at times zero degrees. Thanks

philip mullins

Posted: Oct 09, 2007 08:15 PM

thats getting popular down here as well. with the new codes many homes are 10-15 feet in the air. the codes here say nothing on this matter iether. BUT, i would never leave the site without an ignition barrier. it wont be long before your customer is parking his grill under thier. along with his mower and cans of gas, his boat, etc... none of witch is a good idea with or without foam but, THEY DO IT EVERY TIME. CYA bud!

mason

Posted: Oct 10, 2007 03:55 PM

I received an answer from ICC. Because it is outside of the inhabited area and is not an attic or crawl space it does not require a thermal barrier. However, as Troutkiller points out it is not a bad idea to coat it with an intumescent coating to act as an ignition barrier.

In answer to your question about cold weather condensation, so long as you have a sufficient thickness of closed cell foam (2 inches or more), you should not have a problem with long term moisture problems.

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