NFPA 285 vs. Air Barriers

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Author Message Paul Sweet (Unregistered Guest) Unregistered guest Posted on Monday, August 06, 2018 - 10:46 am:    Does anybody know of a "peel & stick" air barrier (like Henry Blueskin) that has actually been tested to NFPA 285? We are dealing with an OHJ who will not accept engineering evaluations from DrJ, Priest, etc., but only actual test reports and ICC-ESR. I found some NFPA 285 test reports for spray foam insulation and sprayed air barriers on UL & Intertek websites, and ICC has an ESR for Tyvek. Everything else I have found that claims to pass NFPA 285 relies on DrJ or Priest evaluations. Guest (Unregistered Guest) Unregistered guest Posted on Monday, August 06, 2018 - 11:24 am:    Most of them will have been tested in some sort of assembly at this point (eg. Henry Blueskin looks like it has). The bigger question is whether or not it has been tested in your assembly's configuration (which is what the code requires, and probably why the AHJ isn't willing to accept engineering judgments). You'll need to help us out with what the assembly is if you expect to get any useful responses. Ronald L. Geren, FCSI Lifetime Member, AIA, CCS, CCCA, CSC, SCIP Senior Member Username: specman Post Number: 1509 Registered: 03-2003 Posted on Monday, August 06, 2018 - 11:41 am:    NFPA 285 is an assembly test and not a material test. If an air barrier has been tested per NFPA 285, then it was tested as a part of a complete wall assembly, which you would then have to replicate component by component. If the air barrier is the only combustible material in the wall assembly, then the 2015 IBC and later edition have exceptions to the flame propagation requirement in Section 1403.5 that allow air barriers that also function as water-resistive barriers to be used provided the material has a flame spread and smoke-developed indexes of 25 and 450, respectively, total and peak heat release rates and as indicated in the exception, and a heat of combustion of less than 18 MJ/kg. You may have to ask the manufacturer for the test data (if they have it) for the heat release rates and the heat of combustion. Most products will show the FDI and SDI per ASTM E 84/UL 723. Ron Geren, FCSI Lifetime Member, AIA, CCS, CCCA, CSC, SCIP Paul Sweet (Unregistered Guest) Unregistered guest Posted on Monday, August 06, 2018 - 01:24 pm:    Unfortunately the wall is over 40 ft. tall and has polyisocyanurate insulation in the cavity. I know that a NFPA 285 test only applies to the exact combination of products used in that test. If we could find a "peel & stick" air barrier that passed, we could change the insulation to the one used in the test. Tyvek has an ICC ESR, but the contractor would rather not use it, probably because it isn't easy to handle when you're up on a scaffold. Wayne Yancey Senior Member Username: wayne_yancey Post Number: 879 Registered: 01-2008 Posted on Monday, August 06, 2018 - 01:35 pm:    Paul, Contact the manufacturer of the SAM for tested and approved assemblies. Dan DuCharme, 3M Marketing (Unregistered Guest) Unregistered guest Posted on Monday, August 06, 2018 - 03:57 pm:    We have passed several NFPA 285 wall assembly tests with our 3M 3015 Air Barrier Family of products. I'll have someone from our technical team reach out to you with details. I assume you are looking for a permeable solution for this wall assembly based on comments above. We have both permeable and non-permeable membranes available. Jeffrey Potter Senior Member Username: jpotter Post Number: 6 Registered: 02-2017 Posted on Monday, August 06, 2018 - 05:45 pm:    Check out the CI mgfs like Rmax, Johns Manville, Dow Chemical, etc ... They will have the NFPA 285 data sheets that have all materials tested for the CI Product. They are very helpful and useful. Guest (Unregistered Guest) Unregistered guest Posted on Monday, August 06, 2018 - 06:46 pm:    Note that most of the NFPA 285 technical bulletins or design guides that you get from manufacturers (the ones that show a series of "pick one of the following" in order to build up an "approved" system) are relying on engineering judgments. The manufacturers have not tested all the possible combinations you could achieve using those 'choose your own adventure' guides. Instead, they have tested a number of standard and 'worst-case' scenarios and used the information from those tests to extrapolate assemblies that should work if they were to be tested. In other words, assemblies that should work based on the engineer's judgement. Paul Sweet (Unregistered Guest) Unregistered guest Posted on Monday, August 06, 2018 - 07:01 pm:    Guest, that's what we're discovering the hard way. We have contacted several manufacturer's reps, and what they tell or send us always comes back to DrJ or Priest, usually via a small print footnote at the end. Brian Payne Senior Member Username: brian_payne Post Number: 159 Registered: 01-2014 Posted on Tuesday, August 07, 2018 - 07:49 am:    So, I can only find a really low res version that I have in one of my old NFPA 285 presentations, but there is an ICC MEMO dated June 1, 2012 written in response to a BASF letter that states.... “We are in general agreement with BASF’s position that recognition of additional assemblies may be granted based on supplemental engineering analysis and/or smaller scale testing. We think that NFPA 285 test data is needed to establish a baseline performance in order to use engineering analysis or small-scale testing to extrapolate to other assemblies. We would like to continue working with industry in the development of the guidelines needed to achieve this goal.” Brian Payne Senior Member Username: brian_payne Post Number: 160 Registered: 01-2014 Posted on Tuesday, August 07, 2018 - 07:57 am:    Jeffrey Potter Senior Member Username: jpotter Post Number: 7 Registered: 02-2017 Posted on Tuesday, August 07, 2018 - 10:36 am:    Who is the AHJ? I would try and convince them that an ANSI approved testing laboratory like DR. J is just as good as an ICC. I would also get a hold of the MFG. I have had MFG reps come to me and say if I ever have a problem with one of their reports to contact them, and they will reach out to the Plan Checker directly. Ronald L. Geren, FCSI Lifetime Member, AIA, CCS, CCCA, CSC, SCIP Senior Member Username: specman Post Number: 1510 Registered: 03-2003 Posted on Tuesday, August 07, 2018 - 12:04 pm:    Just FYI, ICC-ES does not perform ANY testing. They review the results from required testing performed by accredited testing laboratories when evaluating the product. Just because the ICC or ICC-ES states that engineering analysis may be an acceptable method does not mean that the building official has to accept it. The final approval authority lies with the BO. Now, with that said, the IBC provides for an appeal process within Section 113. Local amendments may change the IBC's requirements, but each jurisdiction should have a means for hearing appeals of decisions made by the BO. Evidence, such as the letter above and baseline test data from the manufacturer, could be used to show the heavy-handedness of the BO when enforcing the code. Appeals take time and cost money, so one will have to weigh the pros and cons. Ron Geren, FCSI Lifetime Member, AIA, CCS, CCCA, CSC, SCIP Sheldon Wolfe Senior Member Username: sheldon_wolfe Post Number: 1016 Registered: 01-2003 Posted on Saturday, August 11, 2018 - 01:38 pm:    Wouldn't it be nice if designers started with what works and then went on to how it looks? ICC has done some great marketing. We have a couple of local officials will not accept engineering judgements from anyone else. Paul Sweet (Unregistered Guest) Unregistered guest Posted on Monday, August 13, 2018 - 12:38 pm:    I think we have finally resolved this. A manufacturer's rep meet with the AHJ and showed them how the products listed as substitutions were evaluated and found to be less combustible than the actual products utilized in the passing NFPA 285 assembly. In other words, the worst case scenario product was tested and the evaluation reports are based on ICC-ES ESR for the passing / approved NFPA 285 wall system. The AHJ also agreed that since DrJ & Priest are ANSI accredited product certification bodies, they will accept their evaluation reports as verification of compliance with NFPA 285. I hope I missed something, but when I looked through UL and Intertek NFPA 285 tests the only air barriers I only found were one liquid-applied air barrier, Tyvek, and multiple manufacturers of sprayed polyurethane foam.