Garage Attic Insulation Questions - Building & Construction - DIY Chatroom Home Improvement Forum

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


Thread Tools Display Modes
Old 10-01-2010, 06:04 AM   #1
Weekend Warrior
Join Date: Jan 2010
Location: Northern Virginia
Posts: 38
Rewards Points: 25

Garage Attic Insulation Questions

Background: Need to insulate attic above attached garage which has finished drywall ceiling. Construction is 2x4 roof trusses 24" OC. Fiberglass R-13 faced insulation has been purchased. Will place 4x8 sheets of plywood atop bottom chord of trusses and use as flooring for storage.

Issue: There are multiple electrical outlets installed in the garage ceiling for lights, etc. and there is 2x4 blocking running between the trusses to which the receptacles are attached (pictured).

Question: Do I place the insulation faced-side down? How do I continue the insulation across the blocking for the outlets? Just slit the paper and pull the insulation apart at those locations or should I actually cut all the way through and use separate pieces in between them? The intent is for the insulation to not stick up above the trusses since flooring will be installed.

FYI - the white cable has been abandoned and removed since the picture was taken. Notice it crossing over the truss. My new wiring is all up to code.
Attached Thumbnails
Garage Attic Insulation Questions-mini-pic-013.jpg  


Last edited by H2O Engr; 10-01-2010 at 06:09 AM.
H2O Engr is offline   Reply With Quote
Old 10-01-2010, 06:42 AM   #2
Join Date: May 2008
Location: Near Philly
Posts: 2,368
Rewards Points: 1,654

In my opinion you should not be using this space for storage of anything of significant weight. That ceiling is designed to hold up the drywall ceiling and is not engineered for storage. The insulation could be split where needed; are you heating the garage space? Typically, the paper side of insulation goes to the warm in winter side of the wall/ceiling.


bob22 is online now   Reply With Quote
Old 10-01-2010, 08:20 AM   #3
Weekend Warrior
Join Date: Jan 2010
Location: Northern Virginia
Posts: 38
Rewards Points: 25

The additional weight is a good point and I am glad it was mentioned. I agree, storing engine blocks and transmissions in the attic is out of the question. It will be used for *light* storage and will try to place items near the load-bearing walls. 4 sheets of 4x8 OSB were used as flooring, so they will remain in addition to the 8 hollow core interior door slabs that were up there to distribute stored items load across a few trusses. How much weight is too much for an *average* truss system?

Garage will be heated. Think it is better to notch the insulation around the the outlets and blocking than to compress it.

Last edited by H2O Engr; 10-01-2010 at 08:34 AM.
H2O Engr is offline   Reply With Quote
Old 10-01-2010, 09:00 AM   #4
Chicago, IL
Michael Thomas's Avatar
Join Date: Jan 2008
Location: Chicago, IL
Posts: 1,037
Rewards Points: 500

If the garage is heated, the vapor retarder goes toward the drywall below the trusses.
Home Inspections, Infrared (Thermal Imaging) Leak Identification and Inspection Services, Roof, Attic, Building, Basement and Foundation Moisture Intrusion and Water Leak Inspections, Troubled Building Consultations - Serving Chicago and Suburbs
Michael Thomas is offline   Reply With Quote

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
Adding insulation and storage to Cape Cod Side Attic turin39789 General DIY Discussions 5 11-08-2010 10:50 AM
Cellulose Insulation Questions... Master Brian Building & Construction 13 09-07-2010 08:09 PM
Attic insulation and soffit venting zacker Building & Construction 1 07-15-2010 10:17 PM
Extending finished attic insulation stops? Mitch H HVAC 2 12-09-2009 11:00 AM
Adding attic insulation pomelo Building & Construction 3 10-22-2009 05:19 PM

Top of Page | View New Posts


Search Engine Friendly URLs by vBSEO 3.6.1