DIY Home Improvement, Remodeling & Repair Forum > DIY Home Improvement > Insulation and Radiant Barriers > Options to Insulate Cold Bedroom Above Garage




Help Support House Repair Talk by donating using the link above.
Reply
 
Thread Tools Search this Thread
Old 08-26-2017, 11:58 AM  
stevevz
Junior Member
Join Date: Nov 2011
Posts: 8
Default Options to Insulate Cold Bedroom Above Garage

Hello all, and thanks in advance for any advice offered.

I am about to tackle a notoriously cold bedroom above my garage once and for all. The current batt insulation up against basement ceiling (or under bedroom floor - depending on how you look at it) that is held in place by wire just isn't cutting it. This insulation is not enclosed (no gypsum board over it).

I found a solution I like that was posted by what appears to be an expert on the subject:

https://buildingscience.com/document...al-performance

However, I want to keep the 2" loss of ceiling height that both options in the article require.

I'd like to go with one of the two options as shown in my images. Is one better than the other?


Click image for larger version

Name:	Option A.png
Views:	63
Size:	54.7 KB
ID:	14490   Click image for larger version

Name:	Option B.png
Views:	62
Size:	66.0 KB
ID:	14491  
stevevz is offline  
 
Reply With Quote
Old 08-31-2017, 08:46 PM  
CallMeVilla
Senior Member
 
CallMeVilla's Avatar
Join Date: Feb 2010
Location: San Diego
Posts: 1,641
Liked 590 Times on 449 Posts
Likes Given: 245

Default

Have you considered closed cell sprayed foam insulation? You get complete coverage and depth which is superior in R value to insulation batts. Why use rigid and batts when you can simply fill the entire joist bay with foam.

Look at the charts from this web site showing R-value of materials and depth.
http://www.greatdayimprovements.com/...lue-chart.aspx


CallMeVilla is offline  
2
People Like This 
Reply With Quote
Old 09-01-2017, 06:47 AM  
stevevz
Junior Member
Join Date: Nov 2011
Posts: 8
Default

Hello. Thanks for the advice. Yes, I have considered the spray foam option. However, I find it far too expensive.
stevevz is offline  
 
Reply With Quote
Old 09-24-2017, 12:45 PM  
frodo
Senior Member
 
frodo's Avatar
Join Date: Aug 2008
Posts: 3,066
Liked 1198 Times on 936 Posts
Likes Given: 415

Default

''I'd like to go with one of the two options as shown in my images. Is one better than the other?''

the answer lies in the R value of what you have.
1/2'' x 4'x8' is an R value of 3

roll insulation with a 19R value will do just fine if you sheet rock the garage ceiling
your problem rat now is the cold air is allowed to circulate around the insulation.
rock the ceiling, stop the air, you will be fine
__________________
Cogito, ergo armatus sum.

My advice is free, If I have helped you and you wish to help the site out with a gift
use this link
http://www.houserepairtalk.com/forum/...faq=supporting
frodo is offline  
 
Reply With Quote
Old 09-24-2017, 05:00 PM  
joecaption
Senior Member
Join Date: Jan 2011
Location: Hartfield VA, VA
Posts: 1,937
Liked 247 Times on 195 Posts
Likes Given: 59

Default

To meet minimum code there should have been 5/8 sheetrock on the ceiling!
It will stop all the air flow.
Need to seal up anyplace where wires or plumbing was run with through the plates with fire proof caulking first.
joecaption is offline  
mudmixer Likes This 
Reply With Quote
Old 09-24-2017, 05:18 PM  
Snoonyb
Senior Member
Join Date: Sep 2006
Posts: 2,400
Liked 418 Times on 370 Posts
Likes Given: 1

Default

Both options call for gyp board, however #1 will give you a warmer floor.
__________________
Illigitimas non-carborundum
Snoonyb is offline  
 
Reply With Quote
Old 09-24-2017, 08:34 PM  
nealtw
Contractor retired
 
nealtw's Avatar
Join Date: Nov 2010
Location: Upper Fraser Valley, British Columbia
Posts: 23,350
Liked 2914 Times on 2555 Posts
Likes Given: 4800

Default

If you go with #1 the insulation can slip down leaving gaps so I would go with #2 no vapour barrier
nealtw is offline  
 
Reply With Quote
Old 09-25-2017, 06:48 AM  
Sparky617
Member
Join Date: Nov 2014
Location: Cary (Raleigh), NC
Posts: 754
Liked 255 Times on 203 Posts
Likes Given: 158

Default

You also need to look at sources of airflow above the room. Sealing outlets and switches, sealing the penetrations into the attic space to stop airflow up. If you go with option one I'd use an adhesive that is safe for the extruded polystyrene and glue it to the underside of the floor to keep it from falling down and compressing the insulation and providing air gaps. If you go with option two, if you have the head room apply it across the bottom of the floor joists, tape any joints and then cover it with 5/8" rock and do at least the tape coat of drywall compound. Personally, I'd go to finish coat and paint the ceiling as it makes the garage look much better to have the walls and ceiling painted out instead of raw drywall.
Sparky617 is offline  
 
Reply With Quote
Old 09-25-2017, 12:03 PM  
bud16415
Fixer Upper
HRT_ADMIN.png
 
bud16415's Avatar
Join Date: Feb 2013
Location: Erie Pa, Pa
Posts: 4,317
Liked 1434 Times on 1098 Posts
Likes Given: 774

Default

I would do option 1 with as thick of foam board as I could find and easily cut and work with. I would cut the pieces for a tight fit and then seal them in at the edges with canned spray foam. If I worried about them falling I would use some strapping screwed into the joists to make a ledge to hold it up. I have found using the sheet foam and then sealing it in with spray foam gives the same result as having the more expensive spray job and is DIY friendly. For additional add the fiberglass with no vapor barrier and then 5/8 Drywall. 5/8 is pretty heavy to work alone with and rent or buy a harbor freight lift. I have done double thickness half inch as well.


bud16415 is offline  
nealtw Likes This 
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

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


Similar Threads
Thread Thread Starter DIY Home Repair Forum Replies Last Post
Garage door weather stripping options? o2284200 Windows and Doors 5 09-02-2013 07:35 AM
Insulate an un-heated attached garage? Quattro Insulation and Radiant Barriers 12 08-24-2013 12:14 AM
Bedroom Really Cold HomeDIYer HVAC 2 01-09-2011 01:20 PM
Garage Floor resurfacing options grins Bricks, Masonry and Concrete 2 11-19-2009 06:55 AM
Converting Garage to Bedroom cibula11 General Home Improvement Discussion 4 08-20-2009 12:49 AM



Newest Threads