I am remodeling a garage into living space. In the attic over the garage, there is about 1.5-2″ of blown in fiberglass insulation. Of course I want to add more. No one around here (Annapolis, Md) seems to DIY blown fiberglass. Can I mix blown in types? Can I just lay blanket fiberglass over the top of the blown in, even though it does not fill the stud bays?
Thanks,
Forrest
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Replies
I would get some blow-in cellulose insulation. Much better than fibreglass, for both retaining heat in winter and blocking radiant heat in summer.
Before you insulate, foam seal all the air leaks in the attic floor plane. i.e. holes from wiring, pipes etc.
Can I blow it in on top of the fiberglass blown in or do I need to remove the fiberglass first?
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Just put it right on top, of any kind of insulation. The side of the bags will show how much in height equates with how much R-factor. Some show the r-factor after settling as well.
Edited 10/29/2004 11:38 am ET by Patchogue Phil
Your garage ceiling was already rocked and had SOME insulation? Here I am in Colorado and my garage has no insulation and no ceiling. Any ceiling joists I have (2X8) are 4' to 6' apart. Certainly not something I would hang gyp board from but obviously someone did in your house if there is a dab of blown in sitting on it. Furring strips maybe? Alot extra from a builder for garage space!
I would double check that garage ceiling framing to make sure nothing (rock) spans more than 16" OC. I thought maybe you had a bedroom over the garage but you said "attic" so... Screws not nails in the gyp board?
I presume you know that there is a difference between habitable space construction and non-habitable (garage) construction and let it go at that.
I used fiberglass batts (unfaced) over the wopping R7 blown in my ceiling (nobody cared in '68) Use a decent respirator, wear a coverall suit of Tyvek, and get the longest 1X2 you can up there to place the batts. (the closer to the outside wall the less space you have to move around). Use something to span the ceiling joists to kneel on. I think I would place the batts perpendicular to the joists, they sag into place. Don't block the vents.
Best conversions I have seen don't have the driveway running up to your former garage door. Cut a few feet off the drive, put in a full width planter about 24" high and fill the rest of the shortened drive with sod. Maybe next year.
I could use a double car garage sectioned door, track and opener. Just drop it off. Thanks, Tyr
Is there any living space currently above this garage?
Any future living space above this garage?
No, no living space above, nor is any planned. The roof covers the garage and a laundry room. I was up there clearing out junk that other homeowners have left and it looks like they blew in fiberglass just over the laundry room. Of course it is about 2 inches deep and spread out all over the place. The garage is currently vented by a eve vent but since we plan on a new roof, I will cut in a ridge went and also soffit vents. That means what ever goes up there I have to keep away from the soffits for venting.
Forrest
Edited 10/29/2004 4:47 pm ET by GasCap
get some corrugated vent chutes so you can get your insulation all the way over the side wall plates.
Air seal everything.