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 02-28-2012, 11:57 AM   #1
Newbie
 
Join Date: Feb 2012
Posts: 7
Share |
Default

Insulate unfinished basement walls?


We just recently finished a large addition/remodel to our home....we went from roughly 900 sq ft to 1,800 sq ft. We had a full basement under the old section and put a basement under the new addition. The two basement sections are connected by an 8' opening. The old basement section only had roughly 7'6" ceiling. In the new basement section we went with 8' ceiling so that we could finish this new section in the future. We don't plan on finishing the old section due to the low ceilings. I do however what to "tighten" things up by insulating the outer basement walls in this old section. I have seen in some homes where the outer walls were insulated below grade with some kind of insulation that had a "reflective" backing and it was just stapled/nailed to the wall. We spend a lot of time in our basement and want to make it as comfortable as possible. My questions: Is this a waste of money/time? If we do this is this the best type of insulating to do? I am open to suggestions/comments. thanks in advance for your responses.

DennyF is offline   Reply With Quote
Old 02-28-2012, 12:02 PM   #2
Member
 
Join Date: Jul 2008
Location: NW of D.C.
Posts: 5,990
Default

Insulate unfinished basement walls?


Since the ground temp. drops the deeper you go, the deeper insulation should be thicker. There is an online graph of this temp. vs. distance but of course I lost the link.

For payback periods of more than 10 years you probably shouldn't do it.

Yoyizit is offline   Reply With Quote
Old 02-28-2012, 12:28 PM   #3
Home Performance
 
HomeSealed's Avatar
 
Join Date: Jan 2008
Location: Milwaukee,WI
Posts: 1,425
Default

Insulate unfinished basement walls?


Quote:
Originally Posted by Yoyizit View Post
Since the ground temp. drops the deeper you go, the deeper insulation should be thicker. There is an online graph of this temp. vs. distance but of course I lost the link.

For payback periods of more than 10 years you probably shouldn't do it.


.... Your best course of action (with bang-for the -buck in mind) would be to airseal the rim joist/sill boxes, then add rigid insulation board on the TOP 4' of the wall. You could go all the way down, but with cost in mind, the top 4' is the most effective. If you are not going to finish the space you'll need to keep fire rating in mind and use a product like thermax that does not need sheetrock over it.
__________________
Replacement Windows, doors, siding, roofing, insulation, and certified energy consulting.
www.HomeSealed.com
HomeSealed is offline   Reply With Quote
The Following User Says Thank You to HomeSealed For This Useful Post:
Windows on Wash (02-29-2012)
Old 02-28-2012, 12:36 PM   #4
Registered User
 
Join Date: Mar 2009
Posts: 9,968
Default

Insulate unfinished basement walls?


Air seal the basement first. Can foam all the wiring/plumbing holes to prevent feeding the "stack effect": http://www.wag-aic.org/1999/WAG_99_baker.pdf

Insulate/air seal the rim joists, a major source of air- both in and outgoing:http://www.buildingscience.com/docum...l_seal_rev.pdf

Insulate with foil-faced foamboard if your local AHJ will allow uncovered: http://www.quadlock.com/technical_li...Insulation.pdf

Pick an insulation system to your liking/budget, pp. 69 on Btu's: http://www.buildingscience.com/docum...study-analysis

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
The Following User Says Thank You to Gary in WA For This Useful Post:
HomeSealed (02-28-2012)
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
framing basement walls with furred ceiling BlueBSH Building & Construction 10 08-05-2011 12:44 PM
Basement: insulate or not pyper Building & Construction 1 01-04-2011 12:10 PM
Advice about Waterproofing Basement Walls Firehawk734 Remodeling 2 12-08-2010 03:23 PM
Insulate basement walls, 1/2 concrete / 1/2 wood frame rovers1973 Building & Construction 1 04-25-2010 05:50 PM
Damp basement walls cjjjer Building & Construction 1 04-02-2010 04:18 PM




Top of Page | View New Posts

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