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 07-29-2012, 10:11 AM   #1
Newbie
 
Join Date: Jul 2012
Posts: 4
Share |
Default

is unfaced fiberglass bad in basement rim joists?


We recently moved into a 32 year old house. The rim joists in the basement are insulated with unfaced fiberglass bats. It looks sloppy, like scrap pieces were just thrown in. I want to remove the old insulation and put new in. I know that most like to use the foam board and seal/caulk the edges. This would take me forever....especially with the hvac and electrical running thru. I have seen no evidence of moisture problems. Can I just take out the old and add new(and more)? If I fill up the whole cavity, will I have to worry about moisture problems? So far, I have done one area. I used the pink, unfaced R-30. I was able to fit about 3 pieces of it in the cavities. Am I overinsulating....or is it not possible to over do it in this area?

ANDYK. is offline   Reply With Quote
Old 07-29-2012, 11:10 AM   #2
Retired from the grind
 
gregzoll's Avatar
 
Join Date: Dec 2006
Location: Midwest - Central Illinois
Posts: 13,973
Default

is unfaced fiberglass bad in basement rim joists?


Unfaced would allow it to breath. If you want to take it a step further, use TigerFoam to seal the bays.

I just used Kraft faced R-13, because I did not want to totally air seal the basement, just wanted to stop cold/hot air convection currents.

__________________
Ren: Now listen, Cadet. I've got a job for you. See this button? Ren: Don't touch it! It's the History Eraser button, you fool! Stimpy: So what'll happen? Ren: That's just it. We don't know. Maybe something bad, maybe something good. I guess we'll never know, 'cause you're going to guard it. You won't touch it, will you?

Last edited by gregzoll; 07-29-2012 at 12:31 PM.
gregzoll is online now   Reply With Quote
Old 07-29-2012, 11:42 AM   #3
Exterior Construction
 
Windows on Wash's Avatar
 
Join Date: Aug 2011
Location: VA, MD, DC
Posts: 5,896
Default

is unfaced fiberglass bad in basement rim joists?


+1

Spray foam it. That will be faster than cutting and stuffing those pieces in.

Last edited by Windows on Wash; 07-29-2012 at 11:43 AM. Reason: Double post
Windows on Wash is offline   Reply With Quote
Old 07-29-2012, 12:33 PM   #4
bbo
Member
 
Join Date: Feb 2010
Location: Packerland !!
Posts: 1,016
Default

is unfaced fiberglass bad in basement rim joists?


i'd second the spray foam. its expensive, but cheaper than my time by far for when I did mine.
bbo is offline   Reply With Quote
Old 07-29-2012, 01:48 PM   #5
Newbie
 
Join Date: Jul 2012
Posts: 4
Default

is unfaced fiberglass bad in basement rim joists?


Thanks for the replies. I've already started w/ the fiberglass.... Just wondering if multiple layers of r-30 unfaced will cause any moisture issues??? I'm fine with overkill, I just dont want to cause any problems.
ANDYK. is offline   Reply With Quote
Old 07-29-2012, 03:00 PM   #6
Retired from the grind
 
gregzoll's Avatar
 
Join Date: Dec 2006
Location: Midwest - Central Illinois
Posts: 13,973
Default

is unfaced fiberglass bad in basement rim joists?


One layer is all you need. No need for overkill. Update with your location, so that people can better help you. Do suggest going over the info at buildingscience.com, which explains the whole process of making the structure work as a whole.
__________________
Ren: Now listen, Cadet. I've got a job for you. See this button? Ren: Don't touch it! It's the History Eraser button, you fool! Stimpy: So what'll happen? Ren: That's just it. We don't know. Maybe something bad, maybe something good. I guess we'll never know, 'cause you're going to guard it. You won't touch it, will you?
gregzoll is online now   Reply With Quote
Old 08-02-2012, 11:53 PM   #7
Registered User
 
Join Date: Mar 2009
Posts: 9,968
Default

is unfaced fiberglass bad in basement rim joists?


If you are in a heating climate, air seal them from the basement. Fiberglass is air permeable, fine after you install foamboard and canned foam the edges. The idea is to stop infiltrating/exfiltrating air from happening. It does not want to breathe. The rim board expands/contracts with the seasons, letting un/conditioned air right through it. At least use faced toward the warm inside.http://www.buildingscience.com/docum...l_seal_rev.pdf

http://www.buildingscience.com/docum...r-penetrations

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
Fiberglass insulation in basement? nateshirk Insulation 38 11-06-2011 09:44 PM
Strengthening Joists Before Basement Finish braverichard Building & Construction 16 06-20-2010 07:28 PM
Floor Joists of different sizes HooKooDooKu Drywall & Plaster 7 02-04-2010 05:43 PM
Exposed fiberglass insulation in partially-finished basement skysurf Building & Construction 1 04-11-2009 09:40 AM
Basement 2x2 furring strips, basement clutter, top plate not attached to floor joists touchsuhas Remodeling 5 12-26-2007 06:01 PM




Top of Page | View New Posts

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