Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Insulation

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 10-14-2013, 07:13 AM   #1
Member
 
Join Date: Oct 2011
Location: Newmarket, Ontario
Posts: 64
Rewards Points: 0
Share |
Default

Basement insulation


Hey guys,

Here is a pic of my basement exterior wall. My current plan is 1" of xps then roxul comfortbatt r14 in stud cavity.

Questions:
What should I do in the area above the foundation wall thats framed?

What should I do in the rim joist area?

Should I run the xps all the way to the floor joists?

Should there be a vapour barrier between drywall and roxul?

Out of curiosity could you just build the wall away from the foundation a 1/2 or so stick comfort batt in (no organics) and then vapour barrier between drywall and studs?
Attached Thumbnails
Basement insulation-image-2178465509.jpg  

RegLearning is offline   Reply With Quote
Old 10-14-2013, 07:16 AM   #2
Member
 
Join Date: Oct 2011
Location: Newmarket, Ontario
Posts: 64
Rewards Points: 0
Default

Basement insulation


Btw I'm in Canada and does anybody know the actually R value code here for a finished basement? The codes I have read are R-12 but I think it was moved to R-20 recently?

RegLearning is offline   Reply With Quote
Old 10-14-2013, 07:58 AM   #3
Exterior Construction
 
Windows on Wash's Avatar
 
Join Date: Aug 2011
Location: VA, MD, DC
Posts: 6,232
Rewards Points: 42
Default

Basement insulation


Ton of threads out there about this stuff.

SPF is easy for the rib joists or cut and cobble rigid foam and seal it to the sides.

No vapor barrier but air tight drywall.

In the areas that are framed, I would want to pull out the existing insulation, seal the exterior sheathing against any air leaks, and install batting.

No need to run roxul unless you really want to. Once you have sealed the cavity against air movement, HD fiberglass batts will do just fine.
Windows on Wash is offline   Reply With Quote
Old 10-15-2013, 07:53 PM   #4
Registered User
 
Join Date: Mar 2009
Posts: 9,968
Rewards Points: 0
Default

Basement insulation


Describe the sheathing/siding, any foam board out there?

Gary
__________________
If any ads are present in my answer above, I do not condone/support/use the product or services listed, they are there against my permission.
Gary in WA is offline   Reply With Quote
Old 10-17-2013, 01:23 PM   #5
Registered User
 
Join Date: Mar 2009
Posts: 9,968
Rewards Points: 0
Default

Basement insulation


Are you still around? Poly wrapped fiberglass batt is bad; http://www.buildingscience.com/docum...Insulation.pdf

Poly sheeting is alright for some areas Canada;http://www.google.com/url?sa=t&rct=j...3dQqtw&cad=rja

Air space is bad letting basement air condense on cold concrete wall, as is fiberglass (air/moisture permeable) alone, per links.

Gary
__________________
If any ads are present in my answer above, I do not condone/support/use the product or services listed, they are there against my permission.
Gary in WA is offline   Reply With Quote
Old 10-17-2013, 03:07 PM   #6
Member
 
concretemasonry's Avatar
 
Join Date: Oct 2006
Location: Minneapolis/St. Paul, Minnesota - Latitude 45.057 Longitude -93.074
Posts: 3,755
Rewards Points: 10
Default

Basement insulation


Watch out for the imaginary red line somewhere on the side of the foundation that is created to make you think there is real deifinte temperature change that the outside air temperature can effect on day by day, hour by hour basis to overcome the huge thermal storage of the soil arounf AND under the basement.

Even R19 can give you only R9 or R10 in many cases IF it is dry and 1% moisture reduces that.

Dick
concretemasonry is online now   Reply With Quote
The Following User Says Thank You to concretemasonry For This Useful Post:
Gary in WA (10-17-2013)
Old 10-18-2013, 07:07 AM   #7
Member
 
Join Date: Oct 2011
Location: Newmarket, Ontario
Posts: 64
Rewards Points: 0
Default

Basement insulation


My thoughts are 2" xps inside rimjoist and false foundation area that's framed above the concrete. Then fiberglass. Then glue 1" foil faced eps to all foundation walls, tuck tape all seams. Then frame 2x4 with sill gasket under and fill with r12 fiberglass then drywall no vapour barrier. Does all this make sense.
RegLearning is offline   Reply With Quote
Old 10-18-2013, 05:08 PM   #8
Exterior Construction
 
Windows on Wash's Avatar
 
Join Date: Aug 2011
Location: VA, MD, DC
Posts: 6,232
Rewards Points: 42
Default

Basement insulation


Whats the point of the foil facing in that capacity and which direction are you pointing it?

I would rather see XPS on concrete in most applications as compared to EPS.
Windows on Wash is offline   Reply With Quote
Old 10-18-2013, 07:14 PM   #9
Member
 
Join Date: Oct 2011
Location: Newmarket, Ontario
Posts: 64
Rewards Points: 0
Default

Basement insulation


Cost is the main reason. Eps with foil face is 1/2 the cost of Xps. Durfoil from Hd is much cheaper than xps from Hd. Trying to remember that although I want to build above the minimum, money still matters!
RegLearning is offline   Reply With Quote
Old 10-19-2013, 10:02 AM   #10
Exterior Construction
 
Windows on Wash's Avatar
 
Join Date: Aug 2011
Location: VA, MD, DC
Posts: 6,232
Rewards Points: 42
Default

Basement insulation


A radiant barrier, without air space, does not provide any benefit in term of R-value. It is a class I vapor retarder though so be cognizant of that.

At the end of the day, you have to have the right amount of R-Value in that wall assembly so while I appreciate the fact that things cost money, even more expensive is having to do it twice.
Windows on Wash is offline   Reply With Quote
Old 10-19-2013, 03:44 PM   #11
Registered User
 
Join Date: Mar 2009
Posts: 9,968
Rewards Points: 0
Default

Basement insulation


EPS is a lot more "green" than XPS, by a long way. You will need to use more to get the same R-value to stop basement air condensation on it. Especially if you fill the cavities in front of concrete/fb with fibrous insulation- requires thicker fb; pp.16;http://www.buildingscience.com/docum...ting-sheathing

If using the foil faced EPS and an empty cavity (double bonus- for vapor barrier and reflective radiation), the foam would need to thick enough to meet local code and prevent condensation on inside face, so R-value is important.

What is the R-value and Type (for density/perms) of foam board? Eg. http://archive.nrc-cnrc.gc.ca/eng/ib.../ctus-n36.html

Then I could figure the minimum thickness fb required (with cavity insulation or without?) to prevent condensation for your location...

Gary
__________________
If any ads are present in my answer above, I do not condone/support/use the product or services listed, they are there against my permission.
Gary in WA is offline   Reply With Quote
Old 10-19-2013, 08:03 PM   #12
Exterior Construction
 
Windows on Wash's Avatar
 
Join Date: Aug 2011
Location: VA, MD, DC
Posts: 6,232
Rewards Points: 42
Default

Basement insulation


+1

EPS is devoid of the blowing agents used in XPS.

That being said, you need the right around of R-value no matter the substrate and EPS does require some sort of facing in most cases as it is not nearly as much of a vapor retarder as XPS.

Last I recall, vapor permeance ratings on EPS are 1.5'ish to 6 depending on the type and formulation.

They are getting better about the blowing agents being used.

http://www.greenbuildingadvisor.com/...oam-insulation

Why not try ISO?
Windows on Wash is offline   Reply With Quote
Old 10-21-2013, 11:52 PM   #13
Registered User
 
Join Date: Mar 2009
Posts: 9,968
Rewards Points: 0
Default

Basement insulation


Just get foil-faced and don't pin-hole the face, Tables 4,7;http://www.google.com/url?sa=t&rct=j...IoU2WbJZYSkvrA

Gary
__________________
If any ads are present in my answer above, I do not condone/support/use the product or services listed, they are there against my permission.

Last edited by Gary in WA; 10-21-2013 at 11:57 PM.
Gary in WA is offline   Reply With Quote
The Following User Says Thank You to Gary in WA For This Useful Post:
RegLearning (10-22-2013)
Old 10-22-2013, 11:12 AM   #14
Member
 
Join Date: Oct 2011
Location: Newmarket, Ontario
Posts: 64
Rewards Points: 0
Default

Basement insulation


Amazing post thanks Gary!
RegLearning is offline   Reply With Quote
Old 10-23-2013, 12:19 AM   #15
Registered User
 
Join Date: Mar 2009
Posts: 9,968
Rewards Points: 0
Default

Basement insulation


You're welcome, we are here to help!

Just to mention need for an egress (escape) window or door while making new living space down there...

Try some "search" in the white box, top right corner; eg. "basement foam board"; http://www.diychatroom.com/search.php?searchid=4282344

Canned foam/XPS the rims, 1" fb under the bottom frame wall plate for thermal/air/capillary break, ADA the drywall, mastic/tape fb seams, canned foam under XPS, fire-stopping every 10' horizontally and at top plate/joist cavities above, glue fb on in 1' square grid pattern to limit air infiltration to same, air-seal all wiring/plumbing holes through floor above (I don't envy you from pic....) foil tape your HVAC supply pipe joints to get all air sent to register, have links for all my answers....

Gary

__________________
If any ads are present in my answer above, I do not condone/support/use the product or services listed, they are there against my permission.
Gary in WA is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Basement Exterior Above Grade Insulation purpasadu Building & Construction 6 02-28-2012 04:42 PM
Insulation in basement floor joists and integrated garage speedster1 Building & Construction 3 12-07-2010 05:44 PM
Old Home - Basement addition insulation vapor barrier question 1870 Building & Construction 0 10-14-2010 07:36 AM
basement insulation advise needed bmartin5150 Building & Construction 1 04-27-2009 04:56 PM
Installing new insulation in my basement and removing the old moldy insulation. Fixitgeorge Remodeling 3 10-17-2006 08:33 PM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.