Insulation Experts Foam or Fibreglass ?shop

[afterburn 549]

OK thats the Q, which would be the better as I have a choice , Using 4'x8' by 4" thick foam, cut to fit between all studs and stufffff or the traditional Fibreglass..stuff
Thanks from Juneau
......Where we have part to partly rainy days with some disorienting clouds to some inland precipitation followed by some more rain right after it stops raining latter to day..
Evening for cast, Winds out of the North humidity @ around 150% , may include a glimpse of the sun @ the 10,0000 foot level.
Around midnight expect more fog and bats crash landing as their sonar is not good enough around here , Do not fret or worry about them as they are completely used to the vile inclement weather and indeed they will repeat this till hibernation sets in and or the smarter ones go where the tides are not so extreme.
There will be a recap later at 10 PM. Refer to this report should you not be able to contain your self and wait..

[Heel n Toe]

I assume you're asking about wall insulation. I don't know which one has the highest r-factor, but use the highest rated one unless cost and/or time of installation causes you to decide otherwise.

In the attic, don't use either one... use blown cellulose and make it as deep as you need to for the r-factor you want.

http://rvalue.net/page5.html

[RWebb]

they havespray foams, now too -- easy 'install'

[MT930]

Alaska

The urethane type, trade name (Corbon) or the others is the right choice. Not only for R- value but for air infiltration.

Works very good here in Montana.

[turbo6bar]

If you already have the foam, by all means, use it, especially if it's closed cell foam (high R value/in). I would caulk the joint between the foam and wall studs. Then again, is this for walls or other? You say studs, implying walls, but 2x4 walls won't accept four inches of foam.

Another alternative is sprayed cellulose for walls and ceilings. I recently used parpac membrane with dense-pack cellulose (not wet spray). The labor is intense, but the cost is very low. Air infiltration is minimal when coupled with foam and caulk. Additionally, cellulose is made from waste products. jurgen

[scottmandue]

I installed air conditioning for ten years and cannot begin to express my deep irrational hatred of fiber glass.

I'm pretty sure he11 is lined with fiber glass.

I guess you know what I vote for.

[billybek]

I had chimed in on the garage thread but will do so again here.
Rock wool or mineral wool insulation is great stuff. Ecologically sound, doesn't burn (kind of a big deal in a garage). Limits infiltration due to the density and is great fire an sound proofing.
You fit it like traditional batt insulation but cut it with a bread knife instead of a blade.
I have used lots of closed cell foam products too and they do have better insulating properties.
You need to make sure that all foams are protected by a fire resistant material (drywall) to insure they won't burn. They are very flammable....
Link to Roxul Flexibatt. http://www.roxul.com/sw47757.asp

[afterburn 549]

I need to be clear , we do have a Home Depot here (Nobody home Depot) LOL . But price wise.. the foam stuff comes about 1//2 the cost (used ) not foiled on either side....but....1/2 the cost...Did i mention that ??
@ 4" I could even double it in the roof.
The small garage I am doing is 2x4 construction...but I am putting 1.5 wood on top of the 2x4 so as to fir it out to a acceptable limit no matter what direction I go
Thanks !

[VincentVega]

I used a mix if foam sheets and fiberglass in my garage. For large areas with no obstructions the sheet was easy to install. Thing is, if you have to make one cut around a box, pipe or something it takes a lot of time. How would you get the sheets into the attic?

I'm thinking about adding some insulation to my attic and like what I read about blown in cellulose. HD lets you use the blower if you buy their insulation.