Insulating Brick Veneer Homes (with 2"x4" wood framing)

[gawain3]

I've done a lot of research and have plenty of experience in renovating homes.  I presently live in a wood-framed home with a brick veneer exterior.  The house was built in 1960.  I have discovered that there is no insulation whatsoever in the wall cavities.  I would like to insulate the house.  Here is what I propose.  Someone please chime in with thoughts and advice.

I want to super-insulate the house in the following order:

(1) remove the 1/2" 2'x10' sheetrock strips that are covered with apx. 1/2" of mud/applied plaster;
(2) clean any debris out of the wall cavities and then install Owens-Corning insulation batts without facing;
(3) install 1" thick 4'x8' pink insulation boards (Owens-Corning), which is considered a vapor retarder, on the exposed studs;
(4) install 7/16" thick 4'x8' oriented strand board for stiffness (for the sheetrock);
(5) install a 6-mil plastic vapor barrier;
(6) install 1/2" thick 4'x10' sheetrock; and
(7) prime and paint the surface with a quality semi-gloss paint.

In the end, the cross section would look like this:  (1) 3.5” thickness of brick, (2) ½” to 1” air gap, (3) ¾” thickness of brown, perhaps petroleum-based, Celotex (buffalo or beaver board?), (4) 3 ½” of pink insulation batts, (5) 1” thickness of pink insulation board, (6) 7/16” thickness of o.s.b., (7) 6-mil vapor barrier, (8) ½” thickness of sheetrock, (9) primer, and (10) semi-gloss paint.

Here are some of my concerns.  First, I would like to use the oriented strand board for stiffness and so that I can apply the sheetrock uniformly.  In addition, the o.s.b. base would allow for a rigid surface for installing heavy pictures etc.  My first question, if I use o.s.b., where should my vapor barrier be?

Here is my second concern.  In my research, a lot has been said about vapor diffusion.  I am concerned that moisture will transit through the brick or mortar, the air gap, the buffalo board, and then come to rest in the insulation batts, thereby causing mold, or some related failure.  I can find no data about insulating a brick veneer home.  Should I be concerned about this possibility?

Lastly, because of insulating the house, the freeze-thaw line of the brick veneer has moved closer to the frame of the house.  Because the brick veneer will be colder than it has been in the past, do I need to worry about spalling, cracks, or just a general degradation of the brick veneer?  This concerns me the most.

Please give me your thoughts, good or bad.

Thanks

[Dale Duffy]

Sorry for chiming in late, sounds good, but I would skip the Six Mil Vapor Barrier, you have a Vapor Barrier using the Owens Corning Styrofoam with VB...tape the joints and be done with it....adding another is asking for possible condensation to occur in my opinion depending on where you live, which I don't know, but any high humidity location could present an issue adding too much Vapor Barrier....let it breath a lil if possible.

People can say all they want about making a house tight, personally I like a house to breath a little, or your asking for problems down the road.

[Dale Duffy]

And from your description you're taking it overboard, no pun intended....but it seems like you will be utilizing a LOT of money when you can get the same insulating values using just Batt Insulation and Styrofoam....DUN ...Done....

[Bill Warner]

I agree with Dale.

Too much vapor barrier can be a bad thing.
No vapor barrier can be a bad thing.

Of more concern would be lack of moisture barrier in the air gap between the veneer and the wall as it doesn't appear that you have addressed in your scenario indicated above.

OSB on the inside prior to drywall seems a bit of overkill as well unless framing is simply substandard, then you are facing other issues.  Hanging heavy objects is what the 2 by stud framing is for.  Now if you're brick on block... well that's entirely a horse of a different color.

[DRG]

and you need a air gap between the veneer and the structural wall

[Barry Adair]

gawain3,
appears you're willing to sacrifice some interior space
i'd check the total costs of what you're proposing vs. fur out the framing and use spray foam insulation
then finish walls in the conventional manner for your region

[PRussell]

All excellent replies.

I would not go through the trouble as described. In the long run it will cause more moisture problems than solved.

I would dense pack cellulose insulation and spend the extra money on air sealing.