Documentation that ccSPF need

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Documentation that ccSPF need "Not Fill" a wall or roof joist cavity. Post New Topic | Post Reply

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CHARLES MAURO Posted: Feb 01, 2010 09:18 AM	Documentation that ccSPF need "Not Fill" a wall or roof joist cavity. Hi Mason, I've run across a building inspector on Long Island, N.Y which is requiring the entire cavity of a wall (2x4 or 2x6) or the roof joist be completely filled with ccSPF so the ccSPF foam touches the sheetrock. His understanding through training with EnergyStar is that once you paint the sheetrock, you now introduce a second vapor retarder, therefore on cold days, moisture can start to condense on the ccSPF in the wall. I explained to him that with a minimum of 2" of ccSPF, this would not happen. Before I go crazy looking for written documentation, which he is requiring, accepting the fact that the ccSPF need not touch the sheetrock, I was hoping you would have such written acceptance in your file somewhere. Thanks
Posted: Feb 02, 2010 04:36 AM	(but the next illogical question for mr inspector is,,and you think this isnt going to happen with a full filterglass or full dense pack rockwool/cellulose type system,,,only the condensation will be at the exterior sheathing interface,,frost in the winter,,water in the summer) you need some computer modeling for a bozo such as this,,maybe hire a consultant with the software (masonknowles.com)to mockup the roof system.. i thru together a wall system(program only looks at walls,,not ceilings) as you describe,,,lacking a few of the exterior roof components(hasty mockup but good enough to show what you ask,,and what you already "knew") that would further put the facts in your favor,,used 4" cc foam over 8.5" batt(reinstall of program without updated material library so cellulostic insulation not in database),,drywall with 12mil paint to interior,,used NY NY (the city so nice they named it twice) with winter conditons of 70 deg in 36 rel humidity in and 13 degree out with 80% rel hum,,and it showed <2 grains of condensation per square foot per day and the dewpoint way out at the exterior of the wall,,no where near the face of the foam...(fyi: h20 characteristic: 1-ounce = 437.5 grains) ask him for his documentation as well so you can answer his questions and address the document,,he wont be able to produce it... ???is his brother a filterglass company owner,,lol) 'dude
mason Posted: Feb 02, 2010 11:55 AM	Yes, there are quite a few docs that can help plus the ICC 2009 codes. Send me your email and I will forward some articles that should help convince them. my email is masonknowles@aol.com

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CHARLES MAURO

Posted: Feb 01, 2010 09:18 AM

Documentation that ccSPF need "Not Fill" a wall or roof joist cavity.

Hi Mason,
I've run across a building inspector on Long Island, N.Y which is requiring the entire cavity of a wall (2x4 or 2x6) or the roof joist be completely filled with ccSPF so the ccSPF foam touches the sheetrock. His understanding through training with EnergyStar is that once you paint the sheetrock, you now introduce a second vapor retarder, therefore on cold days, moisture can start to condense on the ccSPF in the wall. I explained to him that with a minimum of 2" of ccSPF, this would not happen. Before I go crazy looking for written documentation, which he is requiring, accepting the fact that the ccSPF need not touch the sheetrock, I was hoping you would have such written acceptance in your file somewhere.

Thanks

Posted: Feb 02, 2010 04:36 AM

(but the next illogical question for mr inspector is,,and you think this isnt going to happen with a full filterglass or full dense pack rockwool/cellulose type system,,,only the condensation will be at the exterior sheathing interface,,frost in the winter,,water in the summer)
you need some computer modeling for a bozo such as this,,maybe hire a consultant with the software (masonknowles.com)to mockup the roof system..
i thru together a wall system(program only looks at walls,,not ceilings) as you describe,,,lacking a few of the exterior roof components(hasty mockup but good enough to show what you ask,,and what you already "knew") that would further put the facts in your favor,,used 4" cc foam over 8.5" batt(reinstall of program without updated material library so cellulostic insulation not in database),,drywall with 12mil paint to interior,,used NY NY (the city so nice they named it twice) with winter conditons of 70 deg in 36 rel humidity in and 13 degree out with 80% rel hum,,and it showed <2 grains of condensation per square foot per day and the dewpoint way out at the exterior of the wall,,no where near the face of the foam...(fyi: h20 characteristic: 1-ounce = 437.5 grains)
ask him for his documentation as well so you can answer his questions and address the document,,he wont be able to produce it...

???is his brother a filterglass company owner,,lol)
'dude

mason

Posted: Feb 02, 2010 11:55 AM

Yes, there are quite a few docs that can help plus the ICC 2009 codes. Send me your email and I will forward some articles that should help convince them. my email is masonknowles@aol.com

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