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thermal barrier ? Post New Topic | Post Reply
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philip mullins
Posted: Sep 08, 2008 03:36 PM
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thermal barrier ?
dude, i realy hope you are near your cpu right now! here is my problem, i recently sprayed a restaraunt in orange beach, al. 2 x 6 walls. the contract was for 3 inches. but, the lapolla i spray was way outperforming the 4200 bf i figured the job at (nothing new there, good foam every time) and since i wasnt cleaning my tips constantly and all was going smooth we went ahead and passed the extra yeilds onto the client. so he ended up with 3.5 inches. thats how we roll at magnolia solutions/energycraft inc.no, none of that is relevant, i just thought i would give lappy some props for a good product before i mentioned that they are like ALL suppliers and when you need help the guy/gal that you need to talk to is never available and might call you back in a week or so, if at all. how much stock do i have to by, ya know? so i guess i need you to do thier job for them if you dont mind. here,s the deal... client is applying 3/4 plywood to the interior wall studs. covering that with 5/8 sheetrock. i need to convince the fire marshal that this is a good system. where can i find the relevant code (section,paragraph,etc..) info to show the guy? tx in advance. |
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philip mullins
Posted: Sep 08, 2008 04:15 PM
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forgot to mention that this was a closed cell application, if it matters. |
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R Barone
Posted: Sep 08, 2008 09:43 PM
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HI, The best I can tell from your email, the inspector is wrong. We spend all our time with fire and codes. Have the inspector look up IBC 2603.4(ch 26 is plastics). If an approved thermal barrier is over the foam, you meet IBC. Of note, 1/2" sheetrock is an approved thermal barrier..so the 5/8" is over kill. Hope I read your dilemma right and hope this helps.. |
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mason
Posted: Sep 09, 2008 07:08 PM
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Yep, every building code in the country for the last 35 years has required all foam plastics to be protected by a thermal barrier in inhabited areas and has specifically listed 1/2" gypsum drywall as a code approved thermal barrier. The fire marshall may be referring to another section of the code that requires the foam plastic be rated Class I or II in accordance with ASTM e 84. I believe the La Polla foam is rated class I, if not it is at least a class II. Give him a copy of the data sheet showing the flame and smoke spread rating and the section of the code that requires a thermal barrier. It doesn't matter which year the code book is, that part has not changed. |
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philip mullins
Posted: Sep 12, 2008 11:34 AM
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tx guys. for the record, lappy is class 1. i know that we had the thermal barrier requirements met. he just wanted me to tell him where in the code book it stated that the sheetrock or the plywood was sufficient! i bought a book at barnes & nobles but, before i got a chance to look it up i got a call saying that the situation had "worked itself out". hmmm? anyways, alls well that ends well, right? tx again guys. |
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mason
Posted: Sep 12, 2008 03:54 PM
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To clarify your response, plywood is not listed in the codes as a thermal barrier. However, testing conducted by the Society of the Plastics Industry in the 70s determined that 3/4 inch of wood has sufficient thermal resistance to pass a thermal barrier test with sprayfoam (ASTM E 119). I do not have any recent test data that demonstrates this and a code official would most likely want a current test to approve its use. |
