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scott maskell
Posted: Jun 21, 2011 03:19 PM
SPF in "occupied" attic?
Hi all,
I have read dozens of different posts on this site and others regarding this issue. Man, there a lot of differing opinions...
I'm in zone 5 (Omaha). I have a split level house, built in the mid '70s. It has bedrooms over garage. That part of the house is covered by a square hip roof. The main part of the house has a standard gable roof. There are pull down stairs that provide attic access above the bedrooms where there is storage area. There is blown in cellulose in the attic but is woefully inadequate. When I moved in I removed the rotting/molding particle board flooring and replaced it with rolls of bamboo designed for attics hoping the moisture would then be able to exit the vents. Unfortunately I just get condensation on any horizontal surface sitting on top of the bamboo floor. It's occasionally bad enough that when really cold there is frost/ice on the underside of the roof deck. I know I'm leaking heat/moisture badly from below. Since I can't really add any more insulation due to the attic floor I decided to investigate going to an unvented SPF on the roof deck solution. I got quotes from two contractors. One quoted CC, the other OC. From reading lots of posts, it appears to me that since I'm using it for storage that at least this part of the roof needs a thermal barrier on the SPF, correct? Neither quote includes TB or even IB in the quote. I specifically asked one of them and was told that IB was not required in attics and crawlspaces. I want to make sure this meets code so I don't have a mess if I want to sell the house in the future. Assuming TB is needed, what are my options? Drywall/plywood isn't really a practical option on the underside of a slanted hip roof deck. I see there is a coating from TPR2 that is supposed to be TB rated. Is there any other option? Or, any other suggestions?
scott maskell
Posted: Jun 21, 2011 09:03 PM
OK, minor update. I spoke with our local building inspector and as far as he's concerned, an attic being "occupied" by boxes is still just an attic. His position is that it needs to be "living space" before a flame barrier becomes necessary.
angus mcdougald
Posted: Jun 21, 2011 10:12 PM
His position is wrong, but it should be right.....

If you want to store, code says you need coating with most foams.

He says ok it will pass simple

Ignoring liability......

I put a sticker saying no storage in the attic now that I took the Demilec class
I told you no storage sir.... I even installed a sticker up there...

Makes sense that that should work....

Maybe there should be a legal/compliance section in here
Posted: Jun 21, 2011 11:51 PM
as sirbrightness eluded,,,mr codedude is wrong,,
there are a few brands of closed cell foam that have met the testing for left exposed in attics and crawl spaces (and this is the wording sleepy)"access service of utilities only"....no storage,,nada,,zippo,,only trades goin in to service the hvac equip for example,,not all closed cell foams have this testing btw,,and if not they require an ignition barrier(ib) (not thermal barrier tb ) over the foam in this scenerio...the ignition barrier materials allowed are clearly outlined in the code books,,,and some of the foams(again,,not all) now have been system tested with some of the ib coatings and have been granted approval as a foam/ib coating system...
to the best of my hillbilly knowledge as of this post there is one manufacturer who has testing on open cell foam left exposed in attics access service for utilities only,,but i am confident they all will soon,,
re:tpr2: in my code officials jurisdiction they want to see system testing (lucky me eh??)meaning they want to see testing of the ib/tb coating with the specific brand of foam being applied,,,a couple of the coating folks have banner ads on here,,spend some time,,,your welcome doogles...
but in your situation it may not matter as it sounds like your official really aint got a clue about safe application of plastic insulation in his jurisdicition,,
you are well to forward think,,both in the liability(insurance claim in the face of a catostrophic event),,,and from the re-sell when that day comes,,a home inspector worth his salt will pick this one up,,,even if the code official is blind,,,
not havein a clear pix of your attic assembly,,keep in mind you will have to isolate the now conditioned attic assembly from the non-conditioned attic over the main house,,,these will be 2 seperate attic assemblies,,,
hope this helps
scott maskell
Posted: Jun 22, 2011 12:46 AM
thanks fd,
I guess I will have to ask the contractors which brand of foam they use. My concern is that neither of the vendors I have had to my house appear to have much knowledge regarding flame barriers and code requirements. I also have a third contractor, one recommended to me from this site, coming next week. He also didn't seem to have a clear idea on the necessity of flame barriers when asked. Do I just need to be the general contractor here and specify what they need to do?
I don't have a copy of the IRC myself. Can someone point me to the relevant part of the code that specifies that my application should be treated as occupied/conditioned space requiring a TB so that I can educate the SPF contractors and local inspector?
Also, will 3in cc or 6in oc be sufficient for my zone? (I'm confident almost anything will be an improvement over what exists now however).
thx again,
Posted: Jun 22, 2011 10:40 AM
the document is AC377 go to icc-es.org i think and look er up...scroll on down to appendix X,, read and enjoy,,,,
see,,,sleepy its kinda a tough thingy for the foamers,,,we are sellin a "pricey" product that puts us out of reach of the main stream consumer many times cause by golly insulatation is apposed to be the cheapest thing in the house...and then now we have this ib/tb bs in attics and crawls (yes i said bs,,thats where i stand,,we are applying a class 1 fire rated material,,the wood timbers of the structure are class 3 rated,,,flash over??if your house is burnin,,you best be out in a minute or less,,,the wood members will support the combustion and flame like crazy,,flash over indeed),,,
so now we are faced to tell you the consumer we have to add another $1.50 to the system to put this paint on the foam,,,and the price just goes up up up...
many hillbilly foamers choose to ignore the requirements hopeing their code officials are ignorant to the regulations much like yours,,not realizing the risk to their companys future reputation and the potential to liability these applications present to their company,,,this is how it has to be done now,,just the way it is,,,
re: code official,,,give him a bucket of sand and remove his hat with the official city/county logo,,,
re: the foamers,,,mention appendix x,,see what they say,,,ask if you can call their material supplier with them present and ask for its approval in the application you describe,,uncovered,,no ib covering or coating,,should cover it,,,serious
re: depth of foam,,,you do not describe construction frameing dimensions,,,in zone 5 modeling shows we need MINIMUM r20 of an AIR IMPERMIABLE INSULATION to reduce potential for condenstation in the conditioned lid assembly,,
that being said,,,energy star is r50,,you cant put in half as much and expect twice as much in return,,,so,,
this hillbilly foamer likes to apply 5" cc foam when frameing constraints limit depth of application,,,that gets us out to r40 land,,,solid,,strong,,vapor impermiable,,seamless,,no ice dams,,and performance second to no other system out there,,,this lid assembly will be sealed with no leaks to the great outdoors,,,
if we have adequate depth for adequate r value we will install an oc product to 12-15" to again get out to r50 land,,it gets cold in the cornfield,,and darned hot as well,,,
so there ya go sleepyhead,,,hope this helps,,,
Dean Nash
Posted: Jun 22, 2011 10:57 AM
You are more "awake" than many applicators and homeowners, let alone inspectors, and sadly; it's not the applicators fault. A lot of jockeying for position relative to Intumescents has been occurring which has essentially forced the inspectors to "make interpretations" of & on the code.

Proactivity is imperative on your part as well as the part of your chosen applicator. Ask questions that are pertinent to your home. Be specific; "sir, am I interpreting the code as written properly here relative to MY home?" and describe in as much detail as possible YOUR situation. The code is designed to be generic and generalized but as we all know, situations differ from house to house and climate to climate.

By involving code enforcement you and the applicator can & will infuse logic into the legal and often times, provided the inspector hasn't been swayed a particular direction by another, you'll come to a reasonable solution that affords you and the applicator a reduction in your respective liability and the code enforcement official with some tangible and useful information regarding how the code reads that he/she hasn't considered before.

In no way am I suggesting that you mislead the inspector. To the contrary, most inspectors are just not aware of the code or the concerns and don't have the time to really understand it. They are believed to be sponges that can absorb the entirety of the code and have to govern by that code. But in many, if not most, cases; they are governing by the "last version" of the code or by the actions of a predecessor and with your involvement & assistance, they will become more educated.

Remember: with foam, the intumescent has to be matched to that brand and testing results should be posted on the ICC report for that brand. You can research the brands here:

Good luck
scott maskell
Posted: Jun 22, 2011 03:28 PM
Thanks to all for the input.
Joe, unfortunately I was extremely detailed with what I planned on doing when speaking with our local inspector. It didn't help. He was fine with no IB/TB. I'm trying to decide if I get the OK (documented) from the local inspector, to go ahead and skip the IB/TB. I would make sure it was IRC 2006 compliant if there was an actual safety issue, but as foamdude points out it's a theoretical issue here, not a practical one. There is a TB between the SPF and the "real" interior of the house, namely the ceiling drywall. Additionally if I happen to be in the attic when a fire starts I'll know it and I will be out of the house long before any "15 minute thermal barrier" becomes an issue. I guess my real gripe is with the "no storage" provision. In my mind putting Christmas decorations in the attic doesn't change the use significantly over "utility service". No one is actually living up there.
On the other hand I suppose the governing body had to do it or lots of people would be abusing exception by putting in man caves but declaring it as storage. Oh well...
foamdude, thanks for the foam depth info. Question, how much of the price is typically fixed installation versus product? If I get a quote for 3in cc about how much more will going to 5 or 6 be? I assume (hope) it won't double.
thanks again to all
Posted: Jun 23, 2011 10:13 AM
sleepy,,only theoretical amongst us disgruntled foamers,,,
since ac377 the code language is clear as to the use of plastic insulation of which spf falls into that catagory,,,
the subsequent use of ib/tb's over foam is likewise clearly defined,,where it can,,where it cant,,what the exceptions are,,and how to get those exceptions,,
some choose to wear blinders,,some choose not to comply if they can get away with it,,some aint got a clue,,,and the list goes on,,,
ps: i would be surpised if the city of omaha has not adopted irc 2009 by now,,they are really a progressive city,,great grub too!
scott maskell
Posted: Jun 23, 2011 11:24 AM
I get it. Sigh... I guess I'll have to make up a fake invoice to show my wife so she doesn't lose her mind. Ha.
Also, I generalized slightly when I said Omaha. I'm actually in Papillion, on the south side of Omaha. Papillion still uses IRC 2006 (with a few of their own tweaks of course).
Thanks again for sharing your time and knowledge.

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