Insulating Basement With Uneven Walls - Insulation - DIY Chatroom Home Improvement Forum
Advertisement


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

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

Like Tree2Likes
  • 1 Post By chandler48
  • 1 Post By jr1234
Reply
 
Thread Tools
Display Modes
Old 04-13-2019, 04:20 AM   #1
Newbie
 
Join Date: Apr 2019
Posts: 2
Rewards Points: 4
Default

Insulating basement with uneven walls


So, for the past couple of years I've been slowly finishing my basement, and my next step is insulating the walls. I live in a 4C climate, so pretty mild. No obvious moisture problems.

Problem is, I've just noticed that my walls are uneven. All around the perimeter of the basement, the base is about 4' of concrete block wall (height), while the remaining 3' above that is wood paneling. The concrete block protrudes about 7/8" to one inch further into the room than the paneling.

I was planning to use 2" rigid foam to insulate the walls from floor to joists, but now I'm not sure how to address the 7/8 inch gap that would be created between the insulation board and the upper portion of the wall. Any ideas? I'd rather not use spray, so I'm looking for other options (if they're available).

To close that gap, could I add an extra one-inch layer of foam board to the upper section of paneling? Since it's not a precise inch, that might pull me off the wall in some spots. Or could I cut a four-foot section of board to cover the concrete, then put a three-foot section over the paneling, and then seal the seams where they meet in the middle? Any other ideas?

FYI: I do plan to hang drywall on top of the insulation.

Thanks for your feedback.

Last edited by jr1234; 04-13-2019 at 04:36 AM.
jr1234 is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 04-13-2019, 08:41 AM   #2
Naildriver
 
chandler48's Avatar
 
Join Date: Jun 2017
Location: Young Harris, Georgia
Posts: 5,760
Rewards Points: 1,880
Default

Re: Insulating basement with uneven walls


Offset your XPS to take up the 7/8", taping it completely, especially at the lateral break across the top of the ledge. You are building out a stud wall from the block wall, correct? That will even your walls up. I would not adhere any wall covering directly to the XPS. You'll need space for electrical, etc., anyway.
Windows on Wash likes this.
__________________
Larry......
Half of Communications is Listening, and You can't Listen with your Mouth.
chandler48 is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 04-13-2019, 10:36 AM   #3
retired framer
 
Join Date: Jun 2017
Location: Fraser Valley BC Canada
Posts: 21,311
Rewards Points: 10,512
Default

Re: Insulating basement with uneven walls


Install 2" on the bottom and 1" inch on the top build the wall and add 1" between the studs in the top. Start with the fire stop at the top. 1/2" plywood nailed to the joist in to touch the sill plate on the foundation and out to the line of the top plate. So the top plate is nailed up to the plywood.
__________________
Do not use flat bottom gables with scissor trusses.
Nealtw is online now   Reply With Quote
Sponsored Links
Advertisement
 
Old 04-13-2019, 06:37 PM   #4
Newbie
 
Join Date: Apr 2019
Posts: 2
Rewards Points: 4
Default

Re: Insulating basement with uneven walls


Thanks for this feedback.

Yes, I'm building out a stud wall from the block wall. After reading these posts, it seems like it would be okay to leave a gap (the 7/8") uninsulated, between the wood paneling upper wall and the rigid foam. Is that right?

Thanks again.
Nealtw likes this.
jr1234 is offline   Reply With Quote
Old 04-13-2019, 09:14 PM   #5
Member
 
Join Date: Nov 2014
Location: Canada
Posts: 8,935
Rewards Points: 2,628
Default

Re: Insulating basement with uneven walls


You'll need to seal any gap with some spray foam where the insulation ends (top and bottom, possibly sides) to not have a thermal bypass.

A gap can allow for convention, slightly increasing heat loss but not by a lot.
__________________
WARNING: I am not in the business of any trade or topic I give advise on. Follow the advice I post at your own risk. I only have previous diy experience plus good knowledge of theory.
user_12345a is offline   Reply With Quote
Old 04-14-2019, 10:55 AM   #6
Member
 
Join Date: Nov 2014
Location: Canada
Posts: 8,935
Rewards Points: 2,628
Default

Re: Insulating basement with uneven walls


Quote:
A gap can allow for convention, slightly increasing heat loss but not by a lot.
referred to gap between insulation and wall here, not at the edges.
__________________
WARNING: I am not in the business of any trade or topic I give advise on. Follow the advice I post at your own risk. I only have previous diy experience plus good knowledge of theory.
user_12345a is offline   Reply With Quote
Sponsored Links
Advertisement
 
Reply



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
Insulating basement walls, couple quick questions. ponch37300 Insulation 13 06-02-2016 02:46 PM
Basement Insulation uneven walls BasementSkill Insulation 4 01-18-2016 12:23 PM
How to - prevent basement mold crazymountain How To Guides 36 07-23-2014 06:02 PM
Insulating Basement Walls Question rhymlz Insulation 7 02-17-2012 11:07 PM
Insulating interior basement walls brazzle Insulation 3 05-04-2011 07:24 PM




Top of Page | View New Posts