10D-017 OSB 1 HR 10M 031716
March 17, 2016
Memo
TO: Whom It May Concern
FM: Contego International, Inc.
RE: Summary Memo: Contego Fire Barrier For .500 OSB
The following is a summary specific to your project where you will be treating wood elements as part of a 1 hour assembly with a requirement with no combustibility.
APPLICATIONS ON WOOD
Our ASTM-E-119 test on 2x4 decking shows 1:45 duration on raw decking, An additional 30 minutes is added with the use of any acrylic enamel top coat as illustrated in our test data.
This does NOT take into account the additional structural elements that add to your fire resistance.
Our UL-723 from Underwriters Laboratories shows a zero flame spread and zero smoke production overall. UL engineers indicated they have never seen this level of performance from an
intumescent on wood. A subsequent UL-723 extended to 30 minutes (attached) shows a flame spread of 0 and smoke production of 5.
Our ASTM E-84 (UL 723) data on Douglas Fir with only one coat (10 mils dft) shows zero flame spread and limited smoke production over the duration of the test. When compared to the
same test on highly flammable spray polyurethane foam, which was extended to 25 minutes, the substrate was fully protected and flame spread and smoke production flatlined shortly after
the initiation of the test. This indicates that such a test would and could have continued indefinitely.
Our NFPA 286 room burn also indicates long-term survivability on a wood substrate with zero contribution to a room fire. Our combustibility in that test approximates concrete.
Our UBC 26.3 shows excellent thermal resistance on OSB with the cold side temperature never exceeding an average of 1900F until eventually declining after 11 minutes and continuing to
decline throughout the balance of the test period. Results on your materials would logically exceed this kind of performance since your substrate(s) are several times thicker than
the OSB and plywood we tested.
Our UBC-26.2 thermal data illustrated long-term survivability considering the obvious limitation on thermal transfer on OSB, which is, again, lighter and more vulnerable than the materials
you are using. Keep in mind that these tests were focused on thermal transfer. At no point was the wood substrate ignited or even charred. We have not yet been able to generate burn
through conditions for substrates as thin as ½”, even when made of flammable substrates such as OSB.
Wood
Accordingly, you do not need to prime the wood if it is new. Apply a wet film thickness of 15 mils, which will yield a dry film total of 10 mils on all surfaces of the OSB. While this
is overkill, it covers your needs and should resolve any doubts about the ability of your assembly to meet your requirement. In the event of fire, our coating swells up as much as
6 to 8 inches and will seal off any gaps that may exist. Given these performance characteristics, Contego International is certainly willing to certify the performance of our coating
on your assembly for not less than 2 hours in accordance with ASTM-E119 / UL-263 time/temperature curves. Be sure to read and follow the architectural specification for this application
at www.ContegoInternational.com.
Contego has other advantages in that it is not toxic nor it is a carcinogenic material. While the test data supports this recommendation, feel free to experiment with the sample sent
to you to see for yourself using the most demanding test format you can imagine. What you will see is that materials treated with Contego are noncombustible at or exceeding standards
applied to any other material. Hopefully, this answers your questions, but feel free to call if we can be of further service.
Sincerely yours,
Tony Scott
Executive Vice President
Corporate Development
Contego International, Inc.
PO Box 684
Westfield, IN 46074