Hmmm…doing some research for an upcoming remodel on my house. Was thinking about spray foam in the cathedral ceiling and was also thinking about having them spray my totally worthless crawlspace while they were at it. And maybe my basement rim joists.
Some rough numbers I pulled off the net (http://www.ncfi.com/Insulation/JLC_SPF_Artcle.pdf) say that an r-11 spray (low density) is about $1/sq ft of wall. If I extrapolate that to $3.50/sq ft for an R-38 spray on the ceiling and $1.50/sq ft for r-15 on my gable end walls, I come up with a cost of about $10,000 for spraying my addition (about 2400 sq ft of roof and 800 sq ft of gable end wall).
Am I in the ballpark on that number? Sounds like the payback is about 14,000,000 years.
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For 2.7# density polyurethane we're seeing installed prices of about .65/board foot or so. Make sure you distinguish be/t the densities and be/t polyurethane and icynene. Not saying one's better or worse, just know what you're getting and paying for.
So with 2.7# insulation, do you know the R value per inch? I know that 2# produces about R7. If I extroplate, that gives me R9.45 per inch, so I'd need 4 inches in the ceiling to make R38 and that will be $2.60/sq ft. That's certainly better than $3.50, but still pretty high.
Also - can they control the depth of this stuff. I thought they sprayed it in and it expanded rapidly then they sawed if off. Maybe that is low density spray and the high density stuff doesn't act like that.
We control the stuff to the 1/2" or so, but that's in a different application. Did you check out icynene, too. That's easier to cut flush. Offhand I don't know the R of different densities, be/c we choose density for reasons like dent resistance. And realize, too, that R is somewhat misleading. Is R-19 of fiberglass really the same as R-19 of foam? Not hardly. The R of fg is temperature dependent--it's less effective the colder it gets--plus there's a HUGE difference in air infiltration.
>For 2.7# density polyurethane we're seeing installed prices of about .65/board foot or so.
Update: prices have been going up a lot since I posted this in Sept. Don't know what they are now, but they sure aren't .65/bd ft. At least 20% higher, and going up. Oil costs and cost of different blowing agents.
FWIW, this week I'm having urethane applied underneath some floor joists. R38, 256 sf (small job, probably some mobilization costs included here) $593. That's about $2.30 / sf.
"The child is grown / The dream is gone / And I have become / Comfortably numb " lyrics by Roger Waters
RW - what part of the country is that in? I'm in Central NC.
An acquaintance runs a foam business out of Spartenburg SC. He does icynene. Yell if you want the contact.
Yeah, sure you can ask him if Central NC is too far for him to come (Not too many of these guys around so they might travel fairly far for a job). If so please pass along his contact info.
Thanks for the help.
Emailed you the contact info. Good luck.
I pay 70 cents/sf for each one inch of thickness. Used to pay 65 cents. My guy just meters the stuff, and figures up what I owe him based on usage. At R7 per inch, R38 comes to about $3.80 per square foot.
Edited 9/28/2003 6:27:15 PM ET by Mr. Micro
Good to know we're all paying in the same neighborhood.
I can see it goiong on smoother in a flat surfaced environment.
How do you all see this issue of needing R38. I know it is code standard some places but -
That is because in a fibreglass situation where you have leakage and convection stealing from the envelope, the lost heat will be getting sucked through the ceiling/roof area. The excess insulation requirement there is intended to overcome that.
But when we insulate with a sprayed foam package that includes the sills and foundation level, infiltratiuon is almost totally excluded, so exfiltration is reduced also, meaning that the excess insulation at the ceiling is redundant and lost money..
Excellence is its own reward!
The big question is- have you gotten the building inspectors to buy into the "you don't really need R-38 with sprayed foam"? I know it's a new material, and several of the guys around here are starting to use it, but the building inspectors are slow to adapt (as I'm sure you know). What' the concensus up in the great white North?
Bob
Building inspectors?
What is that?
Maine requires local enforcement of a building code if the static population is 2500 or more. Smaller communities work, for the most part, like smaller communities are supposed to work. Builders build on their reputations and the work ethic is strong. All the women are beautifull and all the children are above average too.
;)
Using the faom product is one of the things that has enhanced my reputation when owners get to tell their friend about how snug the house is when the winter gales are snuffing out candles in other homes insulated with fibreglas. One guy brags about how he didn't know the wind was blowing one night because of the sound proofing qualities. He gets lower oil bils than a friend down the raod with R-38 ceiling of cellulose and fibreglas walls in a smaller house.
I took a half day course from the Corbond people (Sales talk as much as education) where part of it was them explainiing some of the tessting records they have and how they are slowly getting some codes to change locally.
I have them go about 1-1/2" at sills perimeter, 2"plus waste in the walls, and about 3" plus in the ceiling.
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Excellence is its own reward!
I know some of you picked up on my original "payback is 14,000,000 years" line and kept reminding me of the other benefits of spray foam. I understand all that and that's why I'm asking about it. I like the fact that the insulation IS the vapor barrier since I live in NC where we 1/3 heat, 1/3 AC, and 1/3 windows are open.
If money permits, In addition to the new 2nd floor, I intend on having the foam sprayed in my crawlspace floor (the crawlspace is wet and moldy - I'm gonna fix that too, but the sprayed insulation sure would make me feel better), the crawlspace wall (cinder block) that is shared with the basement and up in all the rim joist cavities in the basement. Sounds like I should do about 3" on the floor, 2" on the wall, and 1 1/2" in the rim joist cavities.
Thanks again for all the input, it's all extremely helpful.
I am finishing up an addition; wondering about sprayed insulation for several parts (MBR over shop/garage). Did you find someone who you were satisfied with? I am in the RDU area.
Ed
I actually haven't gotten to that point yet. However, I spoke on the phone a few months ago with Tom Hamilton (800-682-4330). That's all I got for now.
where is RDU ?
Russia
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Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
RDU is in central North Carolina.
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"The child is grown / The dream is gone / And I have become / Comfortably numb " lyrics by Roger Waters
I pay between .60 and .70/bd ft depending...
The R-value runs around R7 per inch thickness.
You quoted for R11 so they must figure that it is about 1-1/2" thickness - or they spray an inch, let it overblow a little and call it R-11 while delivering slightly less.
But from what I have seen on application, it is extremely hard to do less than 2" thickness with any consistency.
You may not really need full R-38 because of the fators surronding VB and infiltration issues. That is a whole chapter of studying by itself.
So on my jobs, I am paying a little over $2/sq ft of coverage for a well insulated home.
BTW, there are hundres of other advantages that are only partially related to cost that make it worthwhile. At least my customrs think so.
Excellence is its own reward!
>I pay between .60 and .70/bd ft depending...
>The R-value runs around R7 per inch thickness.
Good to see similar numbers...
>But from what I have seen on application, it is extremely hard to do less than 2" thickness with any consistency.
In a framed environ, I can grok this. On flat roofs and inside our domes with no obstructions to work around, I can show you jobs where the foam surface is as smooth and even as the peel of an orange, and the depth is accurate maybe ± 1/4" to 1/2". On flat roofs, some are using computer-controlled spray arms now. Can't do that on the curves yet.
Hey Paul-- Welcome back!
Here in Chapel Hill, we missed the hurricane by about 30 miles or so. But we paid our dues back in December when the ice storm ripped through. I had the genny ready to go though, but didn't need it this time.
Thanks for the input. I'm weighing such options and one thing that makes such a setup even more cost effective is that I can run the fiberglass myself.
The one guy I talked to today charges $0.80 for the first board foot and then less as you go deeper. 4" is $2.75/sq. ft (R30), 2" is $1.50/sq ft (R15).
Ask your buddy if he will drive to Chapel Hill to do the work (150 miles from Richmond) and if so, email me his contact info.
Thanks --Merc