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2603.7 Foam plastic insulation used as interior finish

sergoodo

SAWHORSE
Joined
Oct 27, 2009
Messages
306
Is an insulation product acceptable that complies with 2603.7 & 2603.7.2 but does not comply with 2603.7.1 & 2603.7.3 acceptable to use?

2603.7 Foam plastic insulation used as interior finish or interior trim in plenums.
Foam plastic insulation used as interior wall or ceiling finish or as interior trim in plenums shall exhibit a flame spread index of 75 or less and a smoke-developed index of 450 or less when tested in accordance with ASTM E84 or UL 723 and shall comply with one or more of Sections 2603.7.1, 2603.7.2 and 2607.3.
2603.7.1
Separation required.
The foam plastic insulation shall be separated from the plenum by a thermal barrier complying with Section 2603.4 and shall exhibit a flame spread index of 75 or less and a smoke-developed index of 450 or less when tested in accordance with ASTM E84 or UL 723 at the thickness and density intended for use.
2603.7.2 Approval.
The foam plastic insulation shall exhibit a flame spread index of 25 or less and a smoke-developed index of 50 or less when tested in accordance with ASTM E84 or UL 723 at the thickness and density intended for use and shall meet the acceptance criteria of Section 803.1.2 when tested in accordance with NFPA 286. The foam plastic insulation shall be approved based on tests conducted in accordance with Section 2603.9.
2603.7.3 Covering.
The foam plastic insulation shall be covered by corrosion-resistant steel having a base metal thickness of not less than 0.0160 inch and shall exhibit a flame spread index of 75 or less and a smoke-developed index of 450 or less when tested in accordance with ASTM E84 or UL 723 at the thickness and density intended for use.
 
It says "one or more," so if the product complies with only one of those three sections, then it is compliant.
 
It says "one or more," so if the product complies with only one of those three sections, then it is compliant.
Thanks! "or" always gives me pause...
Still trying to find a foam product for an interior finish @existing building that will increase R-value and complies with IBC Ch26. I found this product marketed for exposed interior application by a reputable known manufacturer...But cannot confirm compliance.

Can you tell me what I am missing and why this product does comply?
Am I just simply wrong that aluminum DOES qualify as corrosion resistant steel?

Johns Manville's CI MAX® POLYISOCYANURATE FOAM SHEATHING CONTINUOUS INSULATION FOR EXPOSED INTERIOR WALLS OR CEILINGS
Flame Spread ≤25
Smoke Developed ≤450
CI MAX®
2603.7 YES
2603.7.1 NO, not separated with 2603.4 thermal barrier
2603.7.2 NO, smoke-developed index > 50
2603.7.3 NO 1.5mm Aluminum is not corrosion-resistant steel

Link to landing page
https://www.jm.com/en/building-insulation/commercial/foam-board---sheathing/
Link to pdf download
https://www.jm.com/content/dam/jm/g...and Commercial/BID-0142-CI-MAX-Data-Sheet.pdf

Much appreciated!
You have a GREAT 4th of July weekend!
 
Sergoodo,
I am a newbie here, but it reads to me that you need a "yes" to at least one of:
2603.7.1 NO, not separated with 2603.4 thermal barrier
2603.7.2 NO, smoke-developed index > 50
2603.7.3 NO 1.5mm Aluminum is not corrosion-resistant steel
Where you have all 3 as no.
My understanding is that code wants insulation foam to be covered.
 
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