Exterior Wall Insulation (1 Viewer)

rob021275

Guest
Joined
Nov 20, 2004
Messages
2,661
Reaction score
439
Location
Marrero, LA (What the fellas be yellin')
Offline
If anybody has any experience in installing insulation in exterior walls, I could use a little help.

I am having new siding put on next week and want to add insulation where there isn't any currently. I am going to pull the old siding off, put the insulation in the wall cavity, and then put 7/16" OSB sheathing on top of that. Then the contractor is going to install that foamboard on top of the OSB before the siding.

Since the old siding is in bad shape, I want it gone anyway. But the interior walls are newly painted and I don't want to (rather, I won't) pull down the sheetrock.

So, my question is this: I have read online that, generally, the paper side of the insulation should be attached to the inside (house interior side) of the studs with the fiberglass/pink side facing the exterior. That is, unless you live in an hot coastal climate (which I definitely do), in which case the paper side should be on the outside of the house with the fiberglass/pink side adjacent to the back side of the sheetrock. Bottom line: Two different stories have me concerned -- and I'm not even sure the paper qualifies as a "vapor barrier" (it appears to only be plain brown paper). I am using Owens-Corning R-13 for the south wall (which was free courtesy of my neighbor who didn't need it), and will use something stronger for the west wall that takes the real beating from June-October.

I attached a drawing to show what I mean (the colors are for clarification only).

Please tell me "A" is correct (but don't lie to make me feel better), and if it happens that "B" is right, is there any way to attach the paper flange to the inside (interior side) without pulling off the sheetrock?

Thanks in advance.
 

Attachments

  • insulation.bmp
    286.2 KB · Views: 0

Redlands Saints

killing threads daily
VIP Subscribing Member
Gold VIP Contributor
Joined
Sep 9, 2005
Messages
4,056
Reaction score
465
Location
Redlands, CA
Offline
when we did ours we used encapsulated insulation. if you do put the paper towards the inside you can still staple the paper, just push the insulation all the way in and staple the paper to the side of the stud. it doesn't make a perfect barrier but you are putting foam on and I'm assuming a vapor barrier like tyvec wrap as well?
 
OP
rob021275

rob021275

Guest
Joined
Nov 20, 2004
Messages
2,661
Reaction score
439
Location
Marrero, LA (What the fellas be yellin')
Offline
when we did ours we used encapsulated insulation. if you do put the paper towards the inside you can still staple the paper, just push the insulation all the way in and staple the paper to the side of the stud. it doesn't make a perfect barrier but you are putting foam on and I'm assuming a vapor barrier like tyvec wrap as well?

I was debating whether or not I need to use tyvec since I was going to have fiberglass, OSB, that backer board insulation that the contractor was going to use, and then vinyl siding.

My main concerns are:
1) Fire hazard with that paper backing (I don't plan on leaving it exposed, but I'm really concerned near electical wires/outlets)
2) Moisture buidup, which really isn't a problem now without the insulation, so I'm hoping it won't be in the future.
3) Getting something in those south and west walls, which get hot to the touch on the inside during the the afternoons in the summer.

Anything is better than what I have now...which is nothing.
 

Peet

ALL-MADDEN TEAM
Gold VIP Contributor
Joined
Aug 30, 2001
Messages
1,979
Reaction score
17
Age
55
Offline
99% sure that A is correct.
 

FWtex

Hall-of-Famer
Joined
Sep 2, 2003
Messages
4,177
Reaction score
2,029
Offline
Why not just use the spray foam? It may cost more than fiberglass but you would save on the other materials. If you did this I would see about installing a simple plastic sheating inside the studs so the foam does not adhere to the wallboard.

The foam will pay for itself in with the reduced heat/AC usage.
 
OP
rob021275

rob021275

Guest
Joined
Nov 20, 2004
Messages
2,661
Reaction score
439
Location
Marrero, LA (What the fellas be yellin')
Offline
Why not just use the spray foam? It may cost more than fiberglass but you would save on the other materials. If you did this I would see about installing a simple plastic sheating inside the studs so the foam does not adhere to the wallboard.

The foam will pay for itself in with the reduced heat/AC usage.

I actually thought about that, but since I already have the insulation rolls and the siding is in poor shape, I might as well pull it off.
 

Redlands Saints

killing threads daily
VIP Subscribing Member
Gold VIP Contributor
Joined
Sep 9, 2005
Messages
4,056
Reaction score
465
Location
Redlands, CA
Offline
I was debating whether or not I need to use tyvec since I was going to have fiberglass, OSB, that backer board insulation that the contractor was going to use, and then vinyl siding.

My main concerns are:
1) Fire hazard with that paper backing (I don't plan on leaving it exposed, but I'm really concerned near electical wires/outlets)
2) Moisture buidup, which really isn't a problem now without the insulation, so I'm hoping it won't be in the future.
3) Getting something in those south and west walls, which get hot to the touch on the inside during the the afternoons in the summer.

Anything is better than what I have now...which is nothing.

the paper isn't really flammable, I mean anything will burn if it gets hot enough but it shouldn't be a worry. I know what your talking about with the wall getting hot. our master bedroom has one wall that faces south and in the summer the old lath and plaster walls would radiate heat off all night. our house is redwood siding on the outside and had the lath and plaster on the inside with no insulation, hot in the summer and cold in the winter. best money I ever spent on that house was tearing the inside walls out and putting in insulation and drywall.
 
OP
rob021275

rob021275

Guest
Joined
Nov 20, 2004
Messages
2,661
Reaction score
439
Location
Marrero, LA (What the fellas be yellin')
Offline
the paper isn't really flammable.

Yeah...I mean, it says it shouldn't be left exposed or that it could catch, but I figured that was probably a "cover our butts by putting it on there" kind of thing.

Aside from an electical malfunction, I really don't see how that could even be a problem.

It's kind of like things (siding, shingles, etc.) that are wind rated to, say "150 miles per hour". Trust me...if we ever have winds of 150 miles per hour at my house (and it's not a freak tornado), I'll have at least 10 feet of water in it (if it's even standing), and then I really won't care too much about things like that.
 

Create an account or login to comment

You must be a member in order to leave a comment

Create account

Create an account on our community. It's easy!

Log in

Already have an account? Log in here.

Users who are viewing this thread

 

New Orleans Saints Twitter Feed

 

Headlines

Top Bottom