adding insulation to unfinished attic


Old 11-08-03, 09:05 AM
Visiting Guest
Posts: n/a
adding insulation to unfinished attic

I have a ranch house with an unfinished attic (apx. 1,400 sq. feet). I currently have 1 layer of insulation with a r-value of 9. (It also says 1.50 on it, I don't know what that means). It it faced with kraft paper on the bottom. The house was built in 1967 and I'm sure that's the original insulation. It doesn't even fill the entire cavity between the rafters (there is about 3 inches of empty space). I would like to add more insulation. Would it be better just to take out all the old insulation and start from scratch, or just to add more?? Also, how many soffit vents should I have for an attic my size. I only have 2 roof vents (apx. 1 ft. square). I live in the northeast u.s.a. with a long heating season. Another problem I have is the pitch of the roof. It is on a very low angle, so when I am up in the attic it makes it difficult to get close to the edge. That is why maybe I think it would be better just to take out all the old insulation and start from scratch. Any help would be appreciated. Thanks.
Sponsored Links
Old 11-08-03, 10:09 AM
Join Date: Nov 2001
Location: Taylors, SC
Posts: 9,483
Received 0 Votes on 0 Posts
Soffit venting should be something on the order of 1/300 of the square footage of the attic and equalled by the gable end or other outlets. Rough numbers would be 4.7 square feet or ab out a half dozen of the large soffit vents.

Leave the existing insulation, there is no real point in discarding it. Insulation is expensive enough as it is. Besides, it has the vapor barrier on it that you would have to replace in the cramped qurters. I would just blow loose insulation or lay batts to reach the recommended insulation levels for your location. If you have R-9, you may need to add R-30 or more to reach the recommended amount. The recommendation is for R-49 here in the foothills of the Smokies.

Hope this helps.
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

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: