Hi,
I am in the process of insulating by detached garage. I have installed a
Hot Dawg unit heater and insulated the walls with R13 faced fiberglass.
The garage has two floors. The upstairs is unfinished and has dreams of
becoming a game room or studio apartment. When this happens I will install
a seperate heating system, but for now it will be unheated.
My question is what type of insulation should I install in the 2X8, 16" on
center, ceiling of the garage? Since the floor above will be heated
someday, I am assuming unfaced. Should I go with standard R-19 (6 1/4"
thick), R-21(5 1/2" thick) or even something like MIRAFLEX R-25(8 3/4"
thick)?
I live in upstate NY, I believe the design temp is around 10 below.
Thanks,
Jeff

Jeff Guay wrote:
Hi,
I am in the process of insulating by detached garage. I have
installed a Hot Dawg unit heater and insulated the walls with R13
faced fiberglass. The garage has two floors. The upstairs is
unfinished and has dreams of becoming a game room or studio
apartment. When this happens I will install a seperate heating
system, but for now it will be unheated.
My question is what type of insulation should I install in the 2X8,
16" on center, ceiling of the garage? Since the floor above will be
heated someday, I am assuming unfaced. Should I go with standard
R-19 (6 1/4" thick), R-21(5 1/2" thick) or even something like
MIRAFLEX R-25(8 3/4" thick)?
I live in upstate NY, I believe the design temp is around 10 below.
Thanks,
Jeff

Vapor barrier towards the heated side, that is away from the garage.
Not in very warm climates that may be reversed.

--
Joseph Meehan

26 + 6 = 1 It's Irish Math

You need to build to local building code as if the room is heated and garage
is not.


"Jeff Guay" wrote in message
...
Hi,
I am in the process of insulating by detached garage. I have installed a
Hot Dawg unit heater and insulated the walls with R13 faced fiberglass.
The garage has two floors. The upstairs is unfinished and has dreams of
becoming a game room or studio apartment. When this happens I will
install
a seperate heating system, but for now it will be unheated.
My question is what type of insulation should I install in the 2X8, 16" on
center, ceiling of the garage? Since the floor above will be heated
someday, I am assuming unfaced. Should I go with standard R-19 (6 1/4"
thick), R-21(5 1/2" thick) or even something like MIRAFLEX R-25(8 3/4"
thick)?
I live in upstate NY, I believe the design temp is around 10 below.
Thanks,
Jeff

Jeff Guay wrote:
Hi,
I am in the process of insulating by detached garage. I have installed a
Hot Dawg unit heater and insulated the walls with R13 faced fiberglass.
The garage has two floors. The upstairs is unfinished and has dreams of
becoming a game room or studio apartment. When this happens I will install
a seperate heating system, but for now it will be unheated.
My question is what type of insulation should I install in the 2X8, 16" on
center, ceiling of the garage? Since the floor above will be heated
someday, I am assuming unfaced. Should I go with standard R-19 (6 1/4"
thick), R-21(5 1/2" thick) or even something like MIRAFLEX R-25(8 3/4"
thick)?
I live in upstate NY, I believe the design temp is around 10 below.
Thanks,
Jeff


Insulate according to your assumptions. Based on your
assumptions the space above becomes a heated living space
and the bottom is unheated much of the time. I would treat
the ceiling the same as the floor above a craw space. Fully
insulate the ceiling with R-25 insulation with the facing
against the floor. You'll probably get all sort of advice,
with facing, without facing, with it down, with it up. In
the long run, if you are heating the bottom and heating the
top even though it is only periodically, you can probably
get by without facing.