Basement Insulation/Ceiling Joist

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Jcfox00

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Wondering how to go about insulating my basement ceiling joists and what the best R-value would be to insulate my basement walls. Looking to do it myself and have looked into innovative basement systems and insofast. They are expensive drywall alternative and would be easy to install as it seems. and have an r value of 22. I live in Minneapolis so it gets cold in the winter. As you can see my insulation is dirty so do I have air leaks?
We are going to fininsh under the steps, however the wall is underneath the garage, does this wall need to be insulated as well?

Thanks for your help for a newbie...
Joe

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Also, after doing research I may end up insluating the floor as it is currently carpet over concrete. Carpet was new in 2012 so I think it will be fine to keep. Any recommendations on floor panel insulation?
 
Basements are interesting things, are you insulating to help keep the room above warm? Or do you intend to live there? Or for some other purpose?
 
Thanks for the reply! I intend to use as a livable space...media room etc..
 
I also am interested in Insofast . They claim cheaper by the sq of what studs and batts will cost .
 
For what you are doing I don't see how you could beat the Insofast if it is all they say it is.
 
Dirty insulation can be an indictaion of air movement or leaks. We use vapour bearier and any hole in that can be found by looking for dirty insulation. If it is sealed up properly the insulation looks like new even with holes in the outside sheeting. Our outside sheeting always have holes , it's code here.
 
Welcome to the forum, NoverMYhead!

Insofast has been discussed many times.... here is info I posted elsewhere;

But why use such a product compared to rigid foam board sheeting.... unless it is way cheaper or a better insulator.... just too many design flaws, IMO:

"channels for the moisture"- appear to be 3/8"x3/8" cut every 3/4" apart on the back= 1-1/2" x 3/8' missing foam per foot. Double that for 2' wide= 3" x 0.375" = 1.125 sq.in. per 2' panel.

Every 2' is a wiring channel cut (missing foam/R-value again); 3/4" x 3/4" or 0.56 (1/2") x 1" deep ----- added to the back drains = total of 1-1/2" wide where the R-value is only R-4.45---- that is every 2' times a 30' wall = 1.5 x 15= 22.5" almost 2' of only R-4.4 rather than your R-9.8--- full 2" of thickness.

The channels also promote air movement dispersing any moisture vapor through the network of channels- wiring every 2' horizontally and every 16" vertically. Where foam board should be applied with a 1' square grid glue pattern- IMO, to limit air movement behind the foam board; http://joneakes.com/jons-fixit-database/743

http://www.dow.com/webapps/lit/litor...0.pdf&pdf=true

Few other comparisons;

Inso. -- R-4.45 per in vs. R-5 per inch XPS (true R-value, no thermal reduction by 50% at a portion of every 2' panel for drainage).

Inso.- 3.5 perms rating vs. 1.5 or 1.1 perms for others sited. Lower perms equal less water per hour coming through at a slower rate- 50% slower- easier for HVAC to handle. Inso. will have 3 times the volume of moisture coming through, that is the water that doesn't run down the drainage channels to puddle at the bottom plate if you missed a tiny gap under them with canned foam. Wait, no the directions only use glue on the backs in vertical lines to allow convective looping as sited above. No canned foam at the bottom/top to stop any basement air getting between the panel because of the glue bead holding it away from wall OR all the many channels in design to allow air/moisture to condense on cold concrete.

A good building inspector will catch the rated R-=4.45 per inch and product is 2" thick = R-9.8 not R-10 as most locals require- or more- what then- buy more Inso. and double wall? You count the rated R-value of "continuous" footnote "c" not the inside air film= 0.68 plus the 1/2"gypsum board = R-0.45 to get code minimums; and under new codes- min. for Zone 5, 6, 7, and 8 are now R-15- redesign......http://publicecodes.cyberregs.com/ic..._11_sec002.htm
Illinois adopted that 2012 code requiring R-15 below grade in basements; https://www.energycodes.gov/sites/de...gy Codes.pdf
Always check locally for stricter rules with local AHJ.

Just use XPS, save money with a quality installation, product just seems inherent with design flaws to me; http://www.buildingscience.com/docum...Lstiburek_2004

From my answer, #10- here;http://www.diychatroom.com/f19/wall-moisture-126170/ See also the link I supplied in #6.
Gary
 

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