How much better is spray-in foam insulation as compared to fiberglass?
I have a $4000 price for fiberglass vs. a price of $12000 for foam in a 1900 sq. ft. house in the Albany, NY area. Is it worth it and is this price difference accurate?
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There's no comparison as to performance. The foam will do a much better job insulating as it seals each stud bay from any air infiltration. That said, you need to look at the whole picture. If you're installing a 95% efficient heat system, or going to heat with wood that you have a ready supply of{cheap}, you have to look at the payback time.
In my area of NY, {central NY} closed cell foam is running around $3.50 -4.00 per sq. ft. for around a 4" thickness. I utilize a product called BioBased insulation that is partialy soy-based. This runs around $2.00 per sq.ft. for a 4" spray.
Are you looking to do walls and ceilings or just walls? We spray our ext walls, rim joists, and rafter/truss bays over wall plate areas around the baffles, then blow r-50 cellulose in attics.
Beckfella, have you been reading other foam vs FG threads on this forum? I would guess not based on your question. Now this gives me a chukle. Not your question, but I am chuckling and prepared for the onslaught of responses which I know will come.
Be prepared for the answer "I don't care if the foam costs $300,000 vs $4,000 for FG, the foam is better". Ok, I inflated the $300,000 figure, but you will soon understand.
As for a starting point for thinking..... Well, your cost differential is $8000, if you had this $8,000 and invested in a reasonably safe diversified portfolio, you could reasonably earn $800 each year on that money. So if instead you "invest" the money into foam insulation, you will only be better off if you SAVE $800 each year on heating and cooling your house. Now I don't know about your house, but my house is 2400 sq ft and I heated it for $750 plus or minus on natural gas in 2007. So it would be impossible for me to save $800 or even $500 or probably even $300 if I had foam insulation.
Now, I clearly expect there will be some who will tell me that I can save $800 on my $750 bill. That is just the nature of this discussion. So, lay back and enjoy.
Sorry if as a result of this post, future posts will be about my negative foam comments and not directly to your question. Cults are like that.
"Now I don't know about your house, but my house is 2400 sq ft and I heated it for $750 plus or minus on natural gas in 2007. "Maybe your gas meter is broken, or you live down south. Beckfella is in Albany NY, where they have a heating season. If he puts that insulation-of-yesteryear in his walls, he'll likely lose more than $800 more in heat per year than if he did the foam or dense-packed cellulose.Hey, Beck, use the search function and look up all the threads here on FG vs. anything else. If you're building new, why go half-baked on the exterior walls? I'll bet the wife wants a $50K kitchen, huh? Anyway, enough remarks of that sort. You need to provide more detail, if you want more detailed response. What are the dimensions of the wall area covered, not including window area? Open or closed cell foam? How thick?
Sealant applied where the foam can't be applied? Stuff like that.
Chuckle, chuckle, LOL! So it begins. Told ya so.
Where do I live? Northwest and not coastal. Lots of 25 degree days and teens at night, some subzero weather but not a lot.
The point is NO ONE EVER POINTS ANY NUMBERS to their ranting and ravings about foam. Case in point . . . ah . . . well . . . your post.
So again, anyone can do some math. What is your heating bill? You don't like my $750 figure? Ok, use your own. Say it is $1,200, are you going to save the $800 which FINANCIAL ANALYSIS DICTATES is required to make an $8000 invest. ANd listen up, if you don't plan to live in the house forever, the savings MUST be even greater to make it pay. So again if your current bill is $1,200 are you going to drive it to $400 with foam. I doubt it, but the cultist will say your bills will go to ZERO, or well "it is the piece of mind" or ....
LOL.
I have posted these numbers in the past and you ignored them then with the same rant. So here we go again
Complete gut and remodel of 3000 sf office (ranch style house). Prior to remodel monthly utility bills were $800 per month. After remodel with Icynene sprayed in entire envelope of structure bills are $300 per month. Total savings $500 per month or $6000 per year. For this project the difference over fiberglass was paid back in 1.5 years.
Bruce
Hiker, I have never read such figures before. Had I read them I would have said what I am going to say now. Those are STUPID and USELESS figures.
Come on! Who the hellll has an $800 a month bill for heating. I propose that there was ZERO insultation in that house. Heck even your foam figure of $300 is steep.
Since the $800 figure is bogus the $500 savings is bogus.
Before anyone else chimes in here ask yourself about the $800 PER MONTH foolishness.
So the Cultist go on.
Anyone with real figures? Documented, of course.
Notice I stated it was an OFFICE. Notice I said it was a UTILITY BILL not just HEATING BILL. We have to deal with both heating and air conditioning down here. The office was insulated with FG batts prior to demolition. The numbers are very real as I know both the owner before demo and the owner after we completed the remodel. If you are going to enter a discussion at least be open to discuss. Do you have numbers to disprove what I presented?Open your mind man.Bruce
So what does " (ranch style house)" imply? You are what you are.
Hey man, if I were you, I'd go with fiberglass... and, by the way is your first name Dudley? Winterlude, Winterlude, my little daisy,
Winterlude by the telephone wire,
Winterlude, it's makin' me lazy,
Come on, sit by the logs in the fire.
The moonlight reflects from the window
Where the snowflakes, they cover the sand.
Come out tonight, ev'rything will be tight,
Winterlude, this dude thinks you're grand.
If I were you I would continue to Wastefully fritter your money away. You ani't got a pot to p in and you surely won't. I will continue to laugh all the way to the bank. Poverty is a choice, be happy in it.
DoRight are you RedEyedFly in disguise? The ranting you are doing seems very familar to me...
Daniel Neumansky
Restoring our second Victorian home this time in Alamdea CA. Check out the blog http://www.chezneumansky.blogspot.com/
Oakland CA
Crazy Homeowner-Victorian Restorer
If I were you I would continue to Wastefully fritter your money away. You ani't got a pot to p in and you surely won't. I will continue to laugh all the way to the bank. Poverty is a choice, be happy in it.Ummmm, okaaaay... seems that fiberglass has also quickened your wit.Let's see what you make of these numbers:3012 sq' 2 story Fiberglass bid = $7050Open Cell Foam = $8904With me prodding, the HO went with the foam... I know, I know...Their previous home is about 2400sq', w/ fiberglass insulation.All electric house averaged $300/mnFoam house has gas, new total utility average $125... that's with two teenage girls.Just being a very poor dumb carpenter, I might make a mistake in the math... maybe you should do it for everyone...and let me know if you see anybody ahead of you in the bank line that has a real big smile on their face LOL and you know what? He BLAMES it on the foam, danged cultist! Winterlude, Winterlude, my little daisy,
Winterlude by the telephone wire,
Winterlude, it's makin' me lazy,
Come on, sit by the logs in the fire.
The moonlight reflects from the window
Where the snowflakes, they cover the sand.
Come out tonight, ev'rything will be tight,
Winterlude, this dude thinks you're grand.
Is this new construction or renovation? What is the depth of wall cavity? What it the thickness and R-value of the foam that was bid? Of the fiberglass?
Without more information, it's difficult to offer more than a cursory answer.
Cursory answer:
Fiberglass is only marginally better than no insulation, as it's insulative quality diminishes with air movement or vapor diffusion and with decrease or increase in temperature (when it's needed most), as well as with the typically poor quaity installation which leaves many voids and convective loops.
Spray foam (closed cell) has much higher R-value per inch (but overall R-value depends on installed depth), and is an excellent air barrier as well as vapor barrier. There is a point of diminishing returns if you don't insulate inside or outside of the studs, as these will create a thermal bridge through the foam.
I would highly recommend looking into dense-pack cellulose, as it has advantages that neither of the others do (including fire resistance, insect and rodent resistant, and high sound attenuation), as well as being non-toxic and recycled.
Solar & Super-Insulated Healthy Homes
I've done a couple of jobs with foam, and try to do every job with foam. Cost savings/comparisons are not terribly abundant or necessarily accurate, but your energy costs would go down significantly. Is your Hvac roughed in yet? A foam house can survive with a much smaller system which is some savings right off the bat.
My clients that have foam(open cell) and have gone through a winter and a summer in NC say that their overall costs stayed the same even though the sq. footage doubled. The existing houses had little to no insulation, so it's not an accurate comparison to a new fiberglass house, but it will save you money still. For the most part, the savings aren't the reason that my clients are happy with foam, it's because it is really quiet and very comfortable.
If you decide to do it make sure you have a competant Hvac contractor or they will cause big problems for you. They could grossly oversize the unit, which will take care of any cost savings, and they may not understand proper moisture management or exhausting. A foam house is much, much tighter than a fiberglass house and has to have air and moisture dealt with so it won't cause major problems.
Ask the foam company that gave you the estimate to provide some longterm sq. ft. comparisons. They should have some resources.
A cheap way to make fiberglass perform better is to install rigid foam on the exterior over the sheathing. It helps to seal the envelope, which helps the batt performance.
The spray foam is a Caddy, the fiberglass is a golf cart, and the rigid foam sheathing is a Honda.
I just got three quotes on a 2,400 sf house in NC, similar spec (two 1/2 lb Demelac and one 1/2 lb Icenene) roughly $12,500 - $8,500 - and $7,500 pretty big spread there! (the Icenene generally considered to be preferable to Demelak due to it's hydrophobic and fast drying properties was the least expensive.
I did take two 2" cubes of Demelak and Icenene and soak them in the sink under a shampoo bottle over night in the morning the Demelak was MUCH heavier than the Icy and by afternoon the Icy was practically dry and the Demelac still plenty soaked. Not an issue if your houses never leak (but mine do sometimes, so I care.)
The prices are very volatile based on some opportunism in a nascent market (am I allowed to say nascent on BT?) I'd recommend that you get more quotes and also look at using foam on the underside of the roof and to seal the top plate and use fiberglass in the walls and floor as another option.
New York state is too far north to go with "flash and batt" in the walls but in the southern US it's another good way to save some cash and still get the advantages of spray foam.
M
------------------
"You cannot work hard enough to make up for a sloppy estimate."
Did those prices include a sprayed crawlspace? Winterlude, Winterlude, my little daisy,
Winterlude by the telephone wire,
Winterlude, it's makin' me lazy,
Come on, sit by the logs in the fire.
The moonlight reflects from the window
Where the snowflakes, they cover the sand.
Come out tonight, ev'rything will be tight,
Winterlude, this dude thinks you're grand.
No sprayed crawl. We do the tented crawl with fiberglass in the floor.------------------
"You cannot work hard enough to make up for a sloppy estimate."
Tented crawl... how's that work... and why's it better? Winterlude, Winterlude, my little daisy,
Winterlude by the telephone wire,
Winterlude, it's makin' me lazy,
Come on, sit by the logs in the fire.
The moonlight reflects from the window
Where the snowflakes, they cover the sand.
Come out tonight, ev'rything will be tight,
Winterlude, this dude thinks you're grand.
It's a long story best told here. http://www.chandlerdesignbuild.com/files/tentedCrawlComplete.pdf But in a nutshell there is no transfer of conditioned air from the house to the crawl or vice versa (crawl air is poisonous) The sealed crawl is held away from the perimeter foundation 4" (tented) and that perimeter area is ventilated and de-pressurized with a stack vent through the chimney so any moisture that makes it's way under the poly in the sealed crawl can evaporate and be carried away at the 4" gap around the perimeter. Some studies have called the practice of taping the poly into question and I just lap it 12" and staple it to the soil with four pronged ground staples made out of ladder wire.It's controversial so I'd better not say it's "better" than a sealed crawl. It's cheaper than a sealed crawl with exhaust only fan ventilation. It allows for installation imperfection since it doesn't rely on a perfect seal and it allows for occasional moisture to escape. And I think there is less of a transfer pressure differential to push crawl air into the living space than if there were a conventional sealed crawl with a fan blowing conditioned air from the house to the crawl. Mini rant ensues...
Conventional sealed crawl practitioners recommend that people not use vinyl shower curtains in their homes due to the plasticizers in them but then build sealed crawls out of plastic sheets that are full of plasticizers and open a supply duct from the HVAC system into it to pressurize it relative to the house understanding that that air will make its way back upstairs and carry the crawl poly plasticizers and any residual soil gasses and pesticide fumes etc back into the home? Almost as bad as attached garages for indoor air quality in my opinion. My vote for a "Best system" would have to be a taped sealed crawl with exhaust only ventilation and a rat slab to protect the poly. The tented crawl gets you a lot of that goodness for a lower price. Now all you true believers can tear me a new one and call me unprofessional and suggest that I will be facing multiple lawsuits from unhappy customers after their houses collapse from mold infestations. All I can say is "ain't happened yet" I've tried to interest multiple building science groups in doing some testing on it but no takers as of yet. (I haven't gone so far as to offer to pay for a study)I have this in my own house and many others and it seems to be working as planned. I have no real scientific methodology to prove it's better than the alternatives.
------------------
"You cannot work hard enough to make up for a sloppy estimate."
Michael, that's very interesting, and seems simple enough. Not trying to be confrontational ( there's a first!), but when you say crawl space air is poisonous, where are you getting that. I ask because I seal crawls, and have my own shop in mine. Could this be why my bowls are so warped?And, have you been getting approval from Orange and Chatham? Winterlude, Winterlude, my little daisy,
Winterlude by the telephone wire,
Winterlude, it's makin' me lazy,
Come on, sit by the logs in the fire.
The moonlight reflects from the window
Where the snowflakes, they cover the sand.
Come out tonight, ev'rything will be tight,
Winterlude, this dude thinks you're grand.
The assertion that crawlspace air is poisonous goes back to a workshop I took with Southface inst. a decade or more ago. There are termite poisons and the plasticizers from the poly and damp earth humidity trying to escape and the potential for radon. We've been sealing the subfloor paying especial attention to plumbing penetrations under showers and tubs for years. So to go back and open up an AC register in the crawl and allow air to exchange between the house and the crawl totally goes against my grain. I talked with Lstiburek about it last month and he basically said that if it makes me nervous to stick with exhaust only ventilation or passive stack venting by putting a thermal chimney from the crawl up to the top of the chimney (and to the exterior) He did say that omitting the tape was probably a bad idea. But some guys at the National Green Building Standards work group alluded to new research questioning the need for tape and since it's moderately expensive and of dubious value I'll probably continue to omit it. Yes we have been getting approval in Orange. I haven't built in Chatham recently.------------------
"You cannot work hard enough to make up for a sloppy estimate."
Here's some more numbers. This one story home was built a year ago.
1430 sq.ft heated space with 9' ceilings. Insulated concrete slab with radiant heat run by a gas fired modulating boiler system that also is providing domestic hot water. Walls are 4" Bio-Base foam in 2x6 wall w/ 3/4" foam exterior sheathing over 1/2 wood sheathing. Attic is r-50 cellulose w/ foamed in baffle/plate area of trusses.
Thermometer is set at 70 degrees constant{older people who don't like it chilly} and it's located in the Syracuse NY region. February bill just arrived, natural gas for the month,{heat AND hot water} was $ 82.98
Keep in mind as fuel prices increase payback time decreases.
Hmm interesting you say $80 for 1400 sq ft, HIker says four times ($300) that amount for only twice the house. All over the map, I'd say Then my house 2400, old FG with highest month at $180 ish. So gross up the $80 for sqft of 2400 you get $137, so I would save $43 in Feb. Even if that held for five months $200 each year is impossible to justify for an $8,000 additional investment.
Keep in mind, that $80 also includes domestic hot water. I'm not arguing
it might be a long payback. In fact, the pricing quoted does seem high, but I'm not sure exactly what was quoted. In our case, I paid under $2200.00 for our spray foam, installed, verses about $1100.00 for batt insulation. I think this was a great investment. The additional attic insulation when done as part of the original blow-in was not that much more in cost either.
Got it, hot water. That does improve the figures.
The point is that it ani't the greatest thing since sliced bread but from the Cultists you would think otherwise. To be honest, I would love an honest look! But there is less than a zero percent chance here. You have people adding lighting costs to the before costs and then lying about the after costs.
This is the case every time.
Not you, naturally. Your figures and tone indicate otherwise.
I live in the Albany area. Spent about 19k on foam seven years ago. Did not bother to check prices on fg insulation, I had foam in another house and would not consider fg.