Checking Salesmen promise- foam ‘R’ reqd
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Can anyone confirm this info from an Icynene salesman???? He says:
The International Residential Code 2003 and the International Energy Conservation Code specify a minimum ‘R’ value for foam insulation that is lower than FG or cellulose.
Specifically here in Connecticut he claims the code is R11 in walls and R20 in the ceiling. The IRC and IECC are adopted here.
Can anyone confirm or deny this? Any link to info on the web would be a great help!
Thanks,
Stu
Replies
Call your town's building inspector. They should know, and be happy to answer. It's what we pay them for.
Andy
Andy Engel
Senior editor, Fine Woodworking magazine
Other people can talk about how to expand the destiny of mankind. I just want to talk about how to fix a motorcycle. I think that what I have to say has more lasting value. --Robert M. Pirsig
Considering the cost of the material vs. the labor cost of installing it in the first place, I'd simply fill the cavities with Icynene and enjoy phenomenally low heating and cooling costs. Even if you only have 3.5" to play with, that's an R of about 12-13 for the wall.
Keep checking.
Sounds like he is fullabulla
From a practical POV, you need less R-value in foam than with FG batts to save the same BTUs, but I don't believe that codes have been that week for ten or twenty years. You need to ask the local inspector.
You should be asking for 13-15 in walls and 30 in cieling, IMO.
Plus - part of the overall efficiency to be gained with foam is convection controls. You need to have the sills and band joist sprayed in under too.
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I asked the local inspector who didn't know much. Civil servant don't you know... I also followed up and did find out that the IECC does have an alternative formula or method to determine minimum 'R' value. It is the performance method. If you have a product that has proven to perform as well or better than the minimum called for in the spec then that is also acceptable. I am buying the CT state code book tomorrow ($15.90) but I'm not sure they have the latest supplement in it. I might need the IECC and the IRC to really get to the bottom of this. Those are really expensive books though. Better try the library first. Thanks and I'd love to hear more opinons and facts if anything is out there!
Stu
I like that minimum standard equivalency clause! That means the icuy salesman can provide you the printed materials from studies to back up what he says.The only foam company I know of that does that, and has funded studies is Corbond, which is superior to icynene, IMO.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Right! That's exactly what I want... the report that shows me the proof!
Of course the 2 lb foam (Corbond) is superior, R 6+ per inch. The icy has the strong marketing behind it and is R 3.7 per inch.I'm going to dig into this and report back to the board with my findings. This is a huge finding and could make the foam that much more affordable to install!Thanks,
Stu
STRONG MARKETING MEANS BACKING UP ONES CLAIMS WITH TRUTH(dang shift key keeps sticking - gotta get a new keyboard)"Walls that work" is the name of the booklet with all Corbonds references. You could maybe google that up.
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What is this Corbond ? what is it made of? Sprayin place? How does it price out in compare to icy?
Closed cell polyurethyne foam spray in place with added stuff for the insects and such. branded name.
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YOU DON'T HAVE TO SCREAM IT!!thanks for the feedback!
Stu
He's telling you the truth sort of,
Fiberglas insulation has a rating much higher than it winds up being in practice.. Air is free to move thru fiberglas (that's why a lot of furnace filters are made of fiiberglas) As the weather cools off and drops below freezing the air in the wall cavaity moves around due to thermosyphon principles (warm air rises, cold air settles) that air movement drops fiberglas's efficency dramatically. what might have an R11 rating becomes something around an R5 in subzero weather.
That's assuming the batts are perfectly installed something that gets pretty hard to achieve in the real world.. Evan the most diligent installer can and often does over pack a stud bay or leave slight gaps that have no insulating value at all..
Celluloise has a serious problem as well. It settles. Go up into any attic and notice that the celluliose settled 20% or so since it was installed,. that gap at the top of the stud bay has zero insulation value.
Neither insulation has any real R value if it should get damp for any reason..
Given the very real benefits of foam over fiberglas or celluloise you'd be better off with a foam than either of it's two competitors..
It'd be good to see the codes get beyond pure R value. Just by restricting air infiltration you get a HUGE benefit from the foam. I've been regularly frustrated by having a demonstrable advantage in energy usage, but having to justify our methods based on numbers that don't recognize the advantages of foam over other insulators. Hopefully more people will recognize the IECC.
I'm with you Cloud. With energy prices so high it's about time America gets serious with conservation!! That means laws that enforce it and also legislation and code that makes sense like this performance equivalent deal.Same with your domes CH. BTW, what is the 'roof' part of the dome and do you need more insulation there than the 'walls'? I've given an estimate for the foam to a person building a dome and it was really expensive for R19 all over. I told them to get friendly with the town inspector and minimize the 'roof' area. Any presidence you can help with CH? Thanks,
Stu
We do the same thickness all over...3-4". It is a big cost. It is what it is.If I run into a particularly particular plan review person, I talk to them about the building, typically have no trouble having a meeting of the minds on how "efficient" the structures are, and then get their advice on how to list everything to meet the requirements. Once they realize how well the building will perform, and that we aren't cutting corners, they've been good as a whole about accepting the numbers we're able to provide.
Was that "no cutting corners" comment on purpose? Your a killer.
I just came across proof that will save everyone a bunch of money meeting code with the foam!Download the ResCheck software from the http://www.energycodes.gov web site and go to town. This is for checking your situation vs. the IECC code. Most states are based on the International Energy Conservation Code (IECC).Now- on the ceiling and walls choose the "continuous insulation value" and put in say R20. Now in walls do the same and put in R13. Here in CT that is 6.7% better than code!!! This is because the insulation is continuous!! No air infiltration around the batts! The software gives you credit for that!This just knocked 25% off a bid for me, from $19k down to $14.3k.Don't take my word for it check it out for yourselves!You can thank me in the form of a check made out to .....Stu
You can thank me in the form of a check made out to .....
Stu... shame on you!!, the check should be made out to me!!!!!, I am the one that did the leg work that led you to the performance values in the IRC/IECC!!. So what is the final verdict??? am I right??? hmmm... something about Chapter 4 being adopted in MA & CT. Foamers will finally have an equal +/- footing with FBGL guys!!! ;-)
Bigman is correct! He did tell me about it and then I dug through the research until I could prove it.
The software is really sweet. I'll hook you up for this one BM. Stu
>The software gives you credit for that!That's awesome that the numbers reflect reality! Has the potential to make life a lot simpler. Thanks for pointing that out. Check's in the mail.