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DJ Fischer Posted: Jul 28, 2009 06:56 PM	2 questions i have a guy that has a machinery shed that gets a lot of condensation in it. how thick should i foam the building in order to create a good vapor barrier? my second question is when doing and attic what is the best ignition barrier to use? i live in a county in the midwest where we have no codes or code enforcement. still want to make the right application safely tho. any help on these would be much apreciated.. Thanks guys
William Gibson Posted: Jul 29, 2009 06:43 AM	Check with your foam manufacturer and find out at what thickness is their 2 lb. CC spf a vapor barrier. With the product we use, at 1-1½" of CC spf you will create a vapor barrier. As for the ignition barrier try an intumescent coating. Again, you probably can consult with the foam manufacturer to find out what their foam has been tested with. I know of foams tested with FireFree88 coating, and Fireshell by TPR2 just to name a couple. It's always good to use something that had passed certain guidelines especially when tested with the foam you are using. Hope this helps, good luck
mason Posted: Jul 29, 2009 07:44 AM	Good advice newman11, Adding to it, depending on your climate zone, you may require additional closed cell foam to provide the vapor retardency needed. In the coldest climates 2-3 inches are typically recommended. Check the building codes in the 2009 ICC code book. It has a chart that lists the minimum R value required in typical construction when using sprayfoam as a class II vapor retarder in the different climate zones. (note: in high humidity environments such as swimming pools, aquariums,etc or where there is a constant vapor drive in one direction (such as cold storage facilities) even the closed cell foam requires a vapor barrier type membrane or coating over the foam on the warm side. As for ignition barriers. There are a number of intumescent coatings manufactured by a variety of companies that have excellent results in the room corner tests recently adopted by the ICC Evaluation Services. Check ICC Evaluation Services evaluation reports for the various SPF manufacturers for details. ASk your supplier what they have approvals with and if they have performed the latest tests.
DJ Fischer Posted: Jul 30, 2009 04:07 PM	ok thanks guys will do...

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DJ Fischer

Posted: Jul 28, 2009 06:56 PM

2 questions

i have a guy that has a machinery shed that gets a lot of condensation in it. how thick should i foam the building in order to create a good vapor barrier?

my second question is when doing and attic what is the best ignition barrier to use? i live in a county in the midwest where we have no codes or code enforcement. still want to make the right application safely tho. any help on these would be much apreciated.. Thanks guys

William Gibson

Posted: Jul 29, 2009 06:43 AM

Check with your foam manufacturer and find out at what thickness is their 2 lb. CC spf a vapor barrier. With the product we use, at 1-1½" of CC spf you will create a vapor barrier.

As for the ignition barrier try an intumescent coating. Again, you probably can consult with the foam manufacturer to find out what their foam has been tested with. I know of foams tested with FireFree88 coating, and Fireshell by TPR2 just to name a couple. It's always good to use something that had passed certain guidelines especially when tested with the foam you are using.

Hope this helps, good luck

mason

Posted: Jul 29, 2009 07:44 AM

Good advice newman11,

Adding to it, depending on your climate zone, you may require additional closed cell foam to provide the vapor retardency needed. In the coldest climates 2-3 inches are typically recommended. Check the building codes in the 2009 ICC code book. It has a chart that lists the minimum R value required in typical construction when using sprayfoam as a class II vapor retarder in the different climate zones.
(note: in high humidity environments such as swimming pools, aquariums,etc or where there is a constant vapor drive in one direction (such as cold storage facilities) even the closed cell foam requires a vapor barrier type membrane or coating over the foam on the warm side.

As for ignition barriers. There are a number of intumescent coatings manufactured by a variety of companies that have excellent results in the room corner tests recently adopted by the ICC Evaluation Services. Check ICC Evaluation Services evaluation reports for the various SPF manufacturers for details. ASk your supplier what they have approvals with and if they have performed the latest tests.

DJ Fischer

Posted: Jul 30, 2009 04:07 PM

ok thanks guys will do...

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