Codes, Ignition Barriers, Foam Products, Manufacturer's Installation Specs

Comment

Comment by Pat Dundon on July 15, 2011 at 10:50am

I was just asked to pass on a reference to the Spray Polyurethane Foam Association publication AY126 Concerning Thermal and Ignition Barriers.  it can be found at www.sprayfoam.org

Comment by Pat Dundon on July 15, 2011 at 3:51am

Please look at http://www.spraypolyurethane.org/ .  That site is a joint effort of EPA, NIOSH, and the Spray Polyurethane Foam Association.  it is a great clearing house for information on Spray Polyurethane foam.  I disagree with some of what is in your white paper, but understand why and how you present it. 

There are spray applied THERMAL barrier materials available in the market today so foam can be covered with those materials to comply with fire codes.  Google DC-315. 

ICC ESR reports are not great because they are brand specific and they require renewal and retesting periodically.  That makes new products less competitive because the testing costs a lot of money.  New ventures often don't have the cash to cover that, and for established firms the costs of that testing raises the cost of products to us all.  The foam and coating industry is still small enough so large upfront costs cannot get amortized over several tousand or million units.  Manufactures have to pass the costs on to applicators, who pass the costs on the consumers.   

Unfortunately, there are and have been several products that were tested as thermal barriers on other products that have been suggested over foam, but don't work well over foam.  (of course, they don't have ICC ESR's either) In the code, there are several products specified as 'ignition barriers' on foam.  One is 1/4 inch hardboard, another is 1 inch thick mineral wool.  The code lists those products, then says 'or other materials with equal performance'.  In the past year or so, several foam manufacturers have gotten their products tested and found most 2 pound foams will resist fire better than 1/4 inch hardboard.  (I can't find my code book right now, or I would give you the clause).  As a result of that testing, several foam manufacturers have come out with literature saying they meet AC277 and do not require ignition barriers. 

The code specifies ignition barriers in 'attic spaces accessed only for the servicing of mechanical devices where the space does not connect with other attic spaces' (paraphrased) ignition barriers are not as good at resisting fire as thermal barriers are.  To me a mechanical device could be a furnace.  Foam cannot be left exposed in a storage space, it has to have a THERMAL barrier.  Why a mechanical device is less apt to experience a fire than a bunch of your old junk, I do not know.  DC-315 is sold as an ignition barrier and as a thermal barrier.  Thickness at application determines the label.  Ethically, it is more reasonable to always present a thermal barrier as 'preferred' or as a 'best practice', and with the availablilty of DC-315, it is even reasonable.  Several foam manufactuers are now relabeling DC-315 as their own product, getting the ICC report for the combination and going on their merry way. 

The best way is to know the hazards and work to defend against them.  Fumes off foam in fire is not the bigger hazard.  if you have plastics in your home for anything, if you have foam cushions on furniture, or foam pads under carpet, you have a much higher probability of gettting fumes from those plastics burning than you have from foam insulation burning. 

Foam is very good at preventing heat loss and air infiltration.  That means in a fire it will keep the heat in and it will keep the smoke in.  Foam has a realtively low ignition temperature.  The thermal barrier is supposed to hold back heat from the foam for 15 minutes so the fire dept can vent the house and get rid of the heat.  If the thermal barrier is not in place, then foam, especially foam on roof decks, (hot air [smoke] rises) can get hot enough to self ignite very quickly.  I present that to clients, and they pay for a thermal barrier. 

Comment by A. Tamasin Sterner on July 13, 2011 at 9:52am

Thanks, Jennifer.  We thik this will be big news and are hoping to influence contractors to be on the high side of the codes so they don't get bit in the behind sometime.

Comment by A. Tamasin Sterner on July 9, 2011 at 7:11pm

Thanks, Sean. Glad to help.

Comment by Sean Lintow Sr on July 9, 2011 at 5:55pm

Very nice paper & fully agree that it is worth the time to review, I noticed an oversight in one of my articles which I am going to have to correct because of this - Thanks