Insulation help - this is what I get for being nosey

[FastEddieG]

We just moved in several months ago to this 3 year old house. It has a small 3 car attached garage. I already knew the 2 exterior walls and garage door wall did not have insulation in them. There is a bedroom above the garage, in the center.

So I've been getting quotes on blowing insulation into the 3 exterior walls and one of the guys told me he doesn't think the entire ceiling is insulated, only the area directly under the bedroom - not the front or sides. And he said very slowly "minimum code requirement, nothing more nothing less". Those are words I've come to dread hearing in my life

So last night I got nosey and popped a hole in the front of the garage. No insulation in the front 18" or so. So then I popped a hole on a side. No insulation the entire length of the garage 6' wide. I was able to climb up into the 15"x15" hole and investigate some more. So I popped a hole in the other side and near the same thing.

Now here's my initial plans, I'd love to hear your thoughts and suggestions.

In the front of the garage, I'm going to rip down 2' of drywall in the front ceiling, and then put in 6-10" insulation batts along the windblock they have vertical as well as between the joist up to the front wall. These rafters are only ~5' long and run into the front of the bedroom above the garage, never going to an actual peak, but I will still ensure there is airflow from the soffit.

For the bedroom, I can get to the wall on each side within this attic cavity and I saw 3.5" insulation in the walls. There's tyvek on 1/4 of each wall where they just continued wrapped the wall when it was exposed, even what was in this cavity under-roof and wasn't going to be sided. The spots where there isn't tyvek, the insulation is really hanging out of the stud cavity. I'm going to attach cheap 1/2" foam board to hole that insulation in and add a tad more insulation to it and ultimately hold the insulation in place. Then I even thought about attaching another roll of 3.5" insulation to that board, but short of building a stud cavity for it, I could get faced insulation and staple it to the foam board. Would that be bad to add another "vapor barrier" to the wall? Any other way I could add more insulation to those walls short of adding a second wall of studs? If I were to add a second row of studs, I would just use unfaced insulation in the new cavity and then put the foam board on the outside holding the 2 batts in.

So also in these empty attic cavities reside the garage ceiling joists, which would affect my garage space which is what started all of this. The joists are mostly 2x10 running front-back with 3/4" plywood on top. There's a small section of 2x6 in the front area of each side below the roof hip running side to side. I was going to **** 2x10" next to 2x6's and add 3/4" plywood on top to get a continuous floor for storage. As there's no insulation in these, I was going to put down a 6 1/2" R19 kraft faced batt, (kraft face down to the garage), followed by an unfaced 3 1/2" R13 batt to get 10" of insulation in there. I've always heard not to get the 12" R38 insulation and then pack it down.

So in this area, do I need faced insulation? Can I use unfaced? Or, between those joists should I ignore the batts and just get the stuff I can blow in? Maybe even have the guys blow it in there too when they are blowing in the walls.

Thoughts?

Thanks in advance,
-Ed

BTW, I've decided on going with the dense cellulose blown insulation in my garage walls.

 

[idunnosh#t]

That's alot to chew on..O.K 1st see what code requires! Ceiling Might require vapor barrior. Either way faced is o.k .If it's not required blown is an option.($).I think I get the sheetrock removal,it's so you can insulate the top plate without blocking airflow from your soffitts? If possible you may be able to staple those 4' foam vents inplace from in the attic.Then fold a piece of ins. over and push it in place with a broom or something.Save tearout?Bedroom wall..double vap. bar.is a no no. I use 3M SPRAY ADHEISIVE to hold unfaced in a wall. Works Great..just give the nailers a quick spray at the top and work your way down ,never sag. They make fiberglass in I believe 8' wide x what ever length for pole buildings. You could curtian that down over that wall and save furring that wall out as long as you had a good way to secure the top.NO need for add. framing. Not afan of blown in cel. Settling..but short of tear out or foam inj. might be your only option. My $.02 Now I nEEd a nAp...zzzzzzz

 

[FastEddieG]

Pics should help a ton

Here's a pic of the front (the insulation in the ceiling is faced, it just tore off with the drywall).

Here's a pic of the side hole, as well as what I saw inside of it. Once inside the attic, I start taking pics looking right and move to the left.'

Thanks in advance,
-Ed

 

[idunnosh#t]

YOU can do cell. in the attic yourself and save a buck. You can use wire stays to hold that F.G in place or1x or plumbers strap ,strip of cardboard, etc.. I understand the s.r tear out now. That may be your only option as far as that room is involved. Is that room a shed dormer or is that a roof line change? Hope That helps. Good luck

 

[FastEddieG]

Here's a pic of the house so you can see the exterior of the garage/bedroom/roofline.

 

[ghnl]

The Oct/Nov issue of Fine Homebuilding has an article titled, "how to upgrade your home's insulation without gutting". It describes some different options for retrograde insulating.

 

[FastEddieG]

Thanks Eric, I'll check it out. My wife reminded me any insulation we have professionally installed will probably not qualify for the 30% tax incentive, as it's only from specific manufacturers, and labor does not count either. As we'll get a bill from the contractor, that probably won't fly.

So it looks like the contractor will only be blowing insulation in the walls, I'll be doing the ceiling, most likely with fiberglass.

-Ed

 

[idunnosh#t]

That helps alot. I'd say your gonna have do that s.r access in the area in front of those dormer windows.I'm guessing that area won't vent any where other than back to the soffitt itself. Do the process I talked about the vents , ins. over the top plate. Do the same in your storage area. I would put in a pull down ladder at access hole if it would clear your g.d track.2x6's aren't load bearing so u can move 1 over for the ladder frameout. I'd also use 2x4s perpendicular across the top of the 2x6s with a 1/2" p.w ripper tacked on top.Then your 3/4 p.w. Be alot easier than notchin and fightin 2x10s.Now comes the fun x 2. Goodluck