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Ignition barrier required for foam.

The General Description in section 3.0 indicates this is a faced product - aluminum facing. That is likely why. The foam core is not 'exposed', therefore (in conjunction with the other properties) no thermal barrier required. (Not saying I like it BTW, just raising the point...)
 
This particular product appears to have the thermal and/or ignition barrier incorporated... not all of them do
 
Yes an ignition barrier is still required. There is no mention of the material passing the NFPA 286 test as required for foam. E84 does not apply in this case alone.
 
2603.5.7 Ignition. Exteriorwalls shall not exhibit sustained

flaming where tested in accordance with NFPA 268. Where

a material is intended to be installed in more than one thickness,

tests of the minimum and maximum thickness

intended for use shall be performed.

Exception: Assemblies protected on the outside with

one of the following:

1. Athermal barrier complying with Section 2603.4.

2. A minimum 1 inch (25 mm) thickness of concrete

or masonry.

3. Glass-fiber-reinforced concrete panels of a minimum

thickness of 0.375 inch (9.5 mm).

4. Metal-faced panels having minimum 0.019-

inch-thick (0.48 mm) aluminum or 0.016-inchthick

(0.41 mm)corrosion-resistant steel outer facings.

5. A minimum 0.875 inch (22.2 mm) thickness of

stucco complying with Section 2510.
 
FIRE PROTECTIONTHERMAX™ Sheathing is

combustible and shall only be used

as specified by the local building

code with respect to flame spread

classification and to the use of a

suitable thermal barrier. For more

information, consult MSDS, call

Dow at 1-866-583-BLUE (2583) or

contact your local building inspector.
http://www.ifi-in.com/PDFs/Installation-Guidelines/Installation_Guidelines-Dow_Chemical-Thermax_Sheathing.pdf

This was under sheating don't know what product you guy wants to use. Drop a dime and call Blue and find out.
 
The 1 mil aluminum facer doesn't meet exception 4 to 2603.5.7.

One other thing to watch out for is these aluminum facers create an excellent vapor barrier. There will probably be moisture problems if the other face of the wall isn't vapor permeable.
 
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