Spray Foam Or Rigid For Basement Walls? - Building & Construction - DIY Chatroom Home Improvement Forum


Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Building & Construction

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

Reply
 
Thread Tools Display Modes
Old 04-23-2010, 05:47 AM   #1
Member
 
Join Date: Mar 2010
Location: Maryland/North Carolina
Posts: 43
Rewards Points: 25
Default

Spray foam or rigid for basement walls?


I looked at bunch of the forums searching for the answer to the above question and couldn't find a definitive one - maybe there isn't one.

The house is in Western North Carolina, poured concrete walls, 3/4 under ground and has two coats of Dri-Lok. I'm getting ready to stud it out and just want to plan ahead for the wall insulation.

So, is there a consensus, or can I hear the differing opinions?

Thanks as always for the great information.

Advertisement

upinsmoke is offline   Reply With Quote
Old 04-23-2010, 07:10 AM   #2
Member
 
Join Date: Dec 2008
Location: Wilmington, DE
Posts: 3,118
Rewards Points: 2,000
Default

Spray foam or rigid for basement walls?


I like the 2" foamboard with the notches in for furring strips. The strips are screwed (tapcons) to hold the foam, and can also hold the drywall, no need for framing.

Advertisement

Just Bill is offline   Reply With Quote
Old 04-23-2010, 07:35 AM   #3
Member
 
Join Date: Dec 2008
Location: South Western Ontario
Posts: 955
Rewards Points: 500
Default

Spray foam or rigid for basement walls?


I am stuck on this too, there is rigid low density which offers breathability and rigid HD which creates a non breathable barrier and rigid reflective foil faced.
Chemist1961 is offline   Reply With Quote
Old 04-23-2010, 12:14 PM   #4
Member
 
Join Date: Jul 2007
Posts: 1,718
Rewards Points: 1,256
Default

Spray foam or rigid for basement walls?


The most important thing is to make absolutely sure all water/moisture issues are completely resolved before closing it up. Spray foam works great in the rim joist area. Foam board can be used but a little more tedious to fit into the rim joist. On the wall surface foam board is easy to use and usually cheaper than spray foam.
jogr is offline   Reply With Quote
Old 04-24-2010, 06:07 AM   #5
Member
 
Join Date: Mar 2010
Location: Maryland/North Carolina
Posts: 43
Rewards Points: 25
Default

Spray foam or rigid for basement walls?


Thanks. I'm very fortunate in that the basement was totally dry from the start (fingers crossed that it stays that way) and I added the two coats of dri-lok, so I hope I'm good in the moisture department.

So it sounds like foam board for the walls with all seams taped with tyvek or similar. Then, I agree, spray foam is best (or at least less time consuming) around rim joist area - so the question is will a company come in and spray just the rim joist, or do I buy a truck load of spray can foams?

Also, if I do it - is there more than one type of foam? Seems like I read here somewhere about an insulating "fire barrier" type of foam? Any help/experiences in this area would help out.
Rick
upinsmoke is offline   Reply With Quote
Old 04-24-2010, 07:30 AM   #6
Member
 
Join Date: Dec 2008
Location: South Western Ontario
Posts: 955
Rewards Points: 500
Default

Spray foam or rigid for basement walls?


Foam gives off toxic smoke, must be sealed in most areas with a fire barrier min of 1/2 " drywall. You cannot buy any canned foam that I have found for the rim joist which covers a flat area, only as a gap filler or corner bead. There is low and high expansion, ie low is to prevent bulging around windows and doors. If you find a surface coating foam in cans please let me know.Gap filling foam will just drip off a vertical surface if applied thick. You can cut and tuck rigid and seal the edges but I used ROXUL rock wool which is fire resstant and has no itch. Then used rigid foam only for the really tight areas where the wool would not tuck without crushing.
However I did my entire 160 ft rim joist with LOW Expansion foam and a gun with a dial adjustment. I did up and down the inside corners of each joist bay, along the top and bottom edge of the sill plate and the top edge where the floor above sits on and meets the joist. Then I ran out along the floor at each joiust 8-10 inches from the wall. I then stuffed each bay with fresh R23 and tucked back the old R10 on top rather than waste it. I also pulled old tucked fibreglass from around each window and resealed there with foam. I paid special attention to the dryer vent and other perforations. Net cost about $160 and 3 hours labor. Foam trucks want a minimum to show up , at least $500.
Next step, I have sealed under 75 % of my baseboards as well, using latex for easy cleanup in this area.
Net result over 45 % reduction in air loss. 35 yaer old house is far less drafty. One heating contractor told me over 15% of household heat can be lost through a leaky rim joist
I actually got an Extra $$$ BONUS rebate for exceeding audit expectations by over 20% my air sealing measured so well. Air change rate in the house will affect your ventilation system. I started with equivalent to a 268 square inch opening. House is far tighter now. Once I do the basement walls and if I complete the baseboards I may need to add an HRV as my air change has dropped from 6.4 to 3.5 .
Chemist1961 is offline   Reply With Quote
Old 05-02-2010, 05:23 AM   #7
Member
 
Join Date: Mar 2010
Location: Maryland/North Carolina
Posts: 43
Rewards Points: 25
Default

Spray foam or rigid for basement walls?


I'm still exploring/researching the pros and cons of spray vs rigid foam installation. Has anyone heard of any code issues or problems with either high or low voltage wiring being an issue with the spray foam. Either heat build up or any interference?

For you electrical guys - can house or low voltage wiring be run in conduit from the ceiling down the wall to the switches or receptacles? I know it may be above what the code calls for, but it would also eliminate the heat issue - if there is one.

House is in Cherokee County, NC.
Thanks,
Rick

Advertisement

upinsmoke is offline   Reply With Quote
Reply


Thread Tools
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
Putting rigid foam on concrete walls...how to lay DriCore in this setup? ChaoticBliss Building & Construction 14 09-12-2012 06:02 PM
Spray foam insulating joists in basement? peethree Building & Construction 13 11-28-2010 09:54 AM
rigid foam board and height ctkeebler Building & Construction 4 01-09-2010 03:42 PM
Using rigid foam insulation to acheive R-19 in true 2x4 exterior walls? degnem Building & Construction 20 12-15-2009 11:04 AM
Spray in foam insulation leted_82 Building & Construction 3 05-31-2007 11:14 AM




Top of Page | View New Posts