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I am going to be residing my house which was built in 1949, I recieved 2 estimates for insulating the side walls. One contracter recommends certainteed insul-safe because of it’s fire retardence and higher r-value than cellulose. The other contractor recommends “bonded class one wood fiber” (Cellulose?). I was wondering if anyone could tell me which is best and if the fiberglass is worth the $275.00 more that this contractor is asking.
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here's the basic specs on cellulose:
CPSP standard HH-I-515E; 16CFR 1209
ASTM C739-97
Class 1 Building Material
if you want a good product , look for 100% Boric Acid and Borax..
also, it's the other way around.... the cellulose is worth $275 more than the Insul-safe... on this subject
but do a
given your circumstances... i'd choose the Cellulose..
Kermit
*Daniel - the best insulation I've ever seen is BIBS a blown in fiberglass. Great stuff, especially for remodeling. Check it out.
*Well, before this flies off to yet another impassioned discussion, maybe it would be best to search the archives. We've had a lot of discussions on this. Plus, you can check some of your local insulation gurus. I have the feeling that the climate area you are in has a lot to do with how satisfactory certain kinds of insulation are.As for me, I don't like the occasional fire report I read that involves celulose. So, I would use blown in fibreglass.
*well fredb... i kinda thot u were one a the guys that checked his sources... but if yur gonna spread that old chestnut about cellulose and fire spread.. YOU'RE way off base...matter of fact.. it's just the opposite...fiberglass has only better fire protection qualities than NO insulation.... and can't hold a CANDLE to Class 1 cellulose in terms of NOT SUPPORTING flame spread..this has been proven so many times... what do you do for a living ?are u a builder?... have u ever tested or seen any of these products being tested?....are u a fire fighter?are u a lab guy who works for Factory Mutual?have you ever seen a stud wall or attic that was insulated with cellulose AFTER a fire?have you ever seen one that was insulated with fiberglass?you haven't ... or you wouldn't say that...in other words... show me some source that says fiberglass is safer in terms of fire protection than Class 1 cellulose..this question was settled in 1978... geesh..gimme a break
*FredB. Fiberglass does not burn but it does melt.GeneL.
*Agreed fibreglass will melt in a fire. But it will not support combustion.Also, maybe it is a regional thing, but in the North every so often a fire report will state that someone got the cellulose insulation too close to a chimney or some other ignition source causing the fire. Sometime this is a new house, sometimes it is an older one. So, apparently cellulose will at least support combustion.No I'm not a fire marshall, don't even play one on tv. I don't sell either insulation. I'm just doing my best to report the facts so this guy can make up his own mind, or at least do some more personal research to be able to make up his mind.Also, it absorbs water, dries very slowly and can deteiorate under prolonged exposure to moisture according to the insulation fact sheet.
*if...if ..it is reported that someone got the cellulose too close to the chimney and that caused a fire.. then the report was wrong....i do live in the north (6000 degree days)..and i'll give you a little test...you take a hand full of fiberglass insulation and put a penny on the top.. then take a handyman's plumbers torch and heat the penny until it turns red..i'll do the same with a handfull of Class 1 Cellulose....the penny will turn red.. the cellulose will not burn or melt ... nor support combustion..your penny will never get red cause the fiberglass will melt and you'll burn your hand....just like the fiberglass will melt in the wall cavity and then the flame will burn thru the top of the wall and get into the roof structure..with blown in cellulose... after the fire is out, you can pull the sheet rock off the walls.. the surface of the studs will be charred behind the sheet rock.. and perfectly protected where it was in contact with the cellulose..Class 1 Cellulose as a supporter of flame spread is URBAN MYTHOLOGY..the ONLY insulation i've heard of that is more fire retardent than cellulose is Air Krete which is a proprietary form of cement and compressed air......i install a LOT of fiberglass insulation... i think the average r-11 kraft faced stud wall is a joke...the minimum i install is R-11 unfaced , so i can see where the gaps are... most of the time we use an R-13 unfaced batt, and if we can get it we use an R-15 unfaced batt.. but it is always special order, so forget it...given the time and a big enough job, we always use blown in cellulose as our first choice.. and one of the big selling BONUSES is that it is a fire retarder...besides being a superior insulation...my insulation sub.. sells a lot of fiberglass insulation... his builders spec it..but he also sells a lot of cellulose... guess what he uses in his house?
*Well Daniel you've probably gotten a lot more than you asked for. Oddly what kind of insulation to use generates a lot more passion than what one would think.By the way Mike I'm not sure many folks from New England, the Northern Tier states, Canada or Alaska would think you were very far north.
*BTW fred, Rhode Island still qualifies as Cold Climate Construction Area ((6000 deg. days))))....and you can ask our friends south of the Mason-Dixon line if they think we're far enuf NOATH.....hows 'bout it .. we gonna do the penny in the hand test?...the (((passion))) is not about which one u use... its about havin to go back over twenty- year old ground about the SAFETY of a superior product....
*Cellulose.
*I've remodeled alot of homes in Mpls. that have had cellulose insul. I can't say anything bad about it. Never seen it settled in a wall cavity, never seen moisture damage due to condensation. It might be harder to detect because of it's color, but I've never seen evidence of air moving through it like you do with fiberglass batts. I wouldn't hesitate to use it in my own house.
*FredB. Search the archives for my in depth comments on cellulose.However,a few comments. A Swedish building scientist, Per Ingvar Sandberg, found that wetting has only a minor effect on the thermal performance of loose-fill cellulose.Sandberg found that the added moisture caused the R-value to decrease between 8% and 12%, depending on the amount of moisture. his paper was published in volume V of the Thermal Performance of the Exterior Envelopes of Buildings.Moisture is less destructive to cellulose insulation than to the more brittle mineral fiber materials. Several papers presented at the 1978 Durability of Building Materials Conference bear this out. More recently (1984) is a paper by DR. Norman Low,"The Degradation of Thermal Insulating Mineral Fibers."Dr. low foud that under heat and humidity change the long thread-like fiberglass fibers into small segments and granules.We recently learned about the degradation of fiberglass from a homeowner in Missori. Originally 6-inches of fiberglasas had been installed in the attic. The owner had not been in the attic for 20 years. Imagine his shock when he found the 6-iches of fiberglass insulation reduced to a 1-inch pile of dust filled with rat and insect droppings.While cellulose is not prefect is is being subjected to an undeserved reputaion. Again check the archives for my post on cellulose. GeneL.
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I am going to be residing my house which was built in 1949, I recieved 2 estimates for insulating the side walls. One contracter recommends certainteed insul-safe because of it's fire retardence and higher r-value than cellulose. The other contractor recommends "bonded class one wood fiber" (Cellulose?). I was wondering if anyone could tell me which is best and if the fiberglass is worth the $275.00 more that this contractor is asking.