blown in insulation

[picksbigwagon]

cut the hole in the garage ceiling for access, have the drop down ladder but not installed yet, my question is: with using blown in insulation at a depth of 6" so I can put down a plywood floor, am I getting a good R value verses the pink roll type insulation? there is a vapor barrier.....

any hints or tips on blown in?

[Archerysniper]

My tip for the blow in is do it when it's cool that stuff really sticks when your sweaty.

[slammer]

The new blow in stuff is pretty good to work with. Not like the old paper junk. I would spray foam it and then roll out the fiberglass. Foam is only 1 inch thick and has a R value of 6-7 and seals up everything. The glass will then add to your R value. Garage will be alot easier to heat.

[picksbigwagon]

spray foam and then fiberglass? that sounds like it will triple the cost of blown in.

AS, not sweating is exactly why I didn't want to do this project in the summer. Yesterday was absolutely perfect.

You should the draft in the garage when I have the garage door open.

There is one spot that I will take a picture of today, it is an exposed edge (outside the garage walls, and overhang if you will) that is maybe 5 inches wide. no baffles to the eaves and I can see light of day coming up that area. Do I trim down a baffle to fit in there before I blow it in? I feel I should. the rest of the attic has baffles and fiberglass insulation stuffed under the baffles. It is primed and ready for blow in. WHat about compress the insulation down with a plywood floor, am I limiting myself as to how efficient the garage is going to be?

[Eric Wettschreck]

I'm not an expert but you don't want to compress insulation. Rapid deflections of air (Fluffy insulation) is your friend. When you compress it you don't get the rapid deflections / changes in direction / what ever you want to call it, and therefore it actually reduces the R value.

I know where you're going with the floor thing. This stuff will settle after a little time. Let it settle then put down your floor is what I'd do.

[slammer]

Alot of new homes are using foam and MN requires it around the outside walls between the floor trusses. Ya its spendy but well worth the cost. To each his own.

[Tom7227]

IMO folks get too carried away with insulating the garage. Unless you're going to be out there 8 hours a day it just doesn't seem cost effective to me to get all carried away trying to tighten it up to in house standards.

The thing you need to worry about is whether or not your trusses are built to take on any large amount of weight. Too many people try to put too much stuff in the garage attic and end up screwing things up. I'm not an engineer but my suggestion is to do some checking around and make sure that you have enough up there to be able to store stuff. You could really end up making a mess for yourself if you load it up too much.

[NIBOWMAN]

Cellulose insulation actually benifits from some compression, where as fiberglass loses r value when compressed. You will get more Rvalue from 6" of cellulose than you will from the same of fiberglass. I believe about an R20.

[picksbigwagon]

Nibowman, thanks

Tom7227, when we built the house, and it came time for the garage, I told them I wanted trusses that would support a floor and storage. They are 2x6's for the lower board (I am sure there is a more technical term) that the insulation will go into and the boards will go on top of

[Surface Tension]

What you want there a dense pack blown under the floor.

I believe you have the attic trusses. Put blocking or a wad of fiberglass down the center of the room. Install the floor.

There'll be a knee wall where the floor ends. In that location you'll slide the hose under the floor midway across the room(where your blocking is) and start filling, pulling the hose out as the cavity fills.

Insulate between the bottom cord between the knee wall and soffit. You can blown that or use unfaced batts.

I'd personally go with batts. Whatever you do leave air space for air flow from the soffit.

Are you planning sheet rocking the knee wall?

[picksbigwagon]

Surface Tension, there is no knee wall, but I like the idea of putting the floor in and then filling it. I will be using your method for insulating the attic......It's not going to be a finished room I just want to use the attic of the garage for storage and da bride wants a garage heater.........

[crothmeier]

Surface tension has it right! Thats a good way to go about it. A 2x6 bottom chord should be ample for light storage. Typically a garage has a 2x4 bottom chord.

[picksbigwagon]

Well I went pink and itchy today. Used 12 rolls and 12 sheets of 5/8's plywood. I am a little tired right now, but I am glad that it is done. Next will be the ladder installation sometime later this week......