I live in Canada where as you can probably imagine it can get extremely
cold in winter. I have an attached garage (no rooms above it) and the
side of the garage that's attached to the house is finished, however
the two sides that aren't attached are not. I'm thinking of adding
insulation to it (R12) and a vapour barrier, but not putting up
drywall. Is that safe? Do I have to add drywall as well or am I ok
with just the insulation and vapour barrier over it?
Thanks in advance.
I use a garage as a shop. I insulated the walls and ceiling and put 4-year
UV greenhouse polyethylene film over the outside of the south garage door,
which makes for great light and heat when the door is open. I'd like it
to open and close automatically to store solar heat in the slab floor,
except when nobody's home.
Garage door openers are fairly inexpensive, and safe and powerful and
versatile (some people use them to haul boats out of the water :-), and
it's easy to add more foamboard insulation to the doors. It's odd we don't
see more of them used for automatic "movable insulation" in solar heating
systems. I've only heard of one application like that, for a homeless
shelter in Washington state.
The film is attached to the frame with spring wire extrusions and taped
to a PVC pipe so it can roll up for storage under the eave in summertime.
What kind of insulation are you thinking about. Some kinds should be covered
with fire resistant material, others need to be contained to protect the
If it were me, I would use the standard fiberglass insulation with craft
paper on one side and then cover the walls with some quick and easy surface
material such as cheap paneling or masonite.
On Sat, 22 Oct 2005 10:48:53 -0400, "Robert L. Haar"
I'd do the same. Pegboard is preferred and I have seen pegboard that
looks lile panelling (woodgrain). I want the garage walls to be
useful, not easily damaged like drywall.
If you do use drywall and the garage is on a poured slab, dont waste
your time taping the joints, they will only crack. Slabs move. They
do sell drywall with built in wallpaper made to be installed without
taping the joints and looks nice. The only reason I can see drywall
as an advantage is fire protection. Of course you could put pegboard
over it, but would have to fir it out, and double the cost.
I live in Winnipeg and have my attached garage insulated - door, walls &
ceiling. I definately enjoy having insulated it but here are a couple of
other thoughts on insulating garages.
* The retained heat from a warm engine keeps the garage warmer than the
outside. In winter this leads to snow melting off the car and dripping onto
the floor. That results in puddles of salt laden water which don't always
run out the garage door (unless your floor is well sloped to the outside).
My garage floor was initially sloped to 2" over 20 feet. Some setting must
have occurred as I had water accumulating along the sides and in the outside
corners of the garage - so this year I added a skim coat of 1/4" concrete
along the garage floor sides with the theory it will prevent the water from
collecting on the sides/corners (we will see how that works out very soon).
* The warmer temperatures facilitate rust - so you might want to look into a
rust treatment for your vehicle. I use Rust Check every year.
* You may need a floor squeegee to sweep the excess water out every so
Using an insulation and vapor barrier that does not require coverage is
OK, but not all possibilities pass that test. I covered mine with peg
board. While that does not provide the protection that might be needed for
some materials, it does provide a lot of storage space.
If its a garage, you should put fire rated drywall on. In case of a
fire, all that insulation and vapor barrier will catch on fire quickly.
Drywall is cheap enough and easy to put on. You don't even have to
paint it if you don't feel like.
Kind of depends on the insulation. I have yet to see fiberglass
insulation catch fire. The problem with a vapor barrier is more likely to
be the poisonous gases it may give off if it burns, but then then in a
garage, if you have a fire, I doubt if that is going to be your concern.
Few if any local codes require fire brakes on exterior walls of a garage.
If one uses fiberglass batts, it ain't going to
catch on fire, and the fiberglass will protect the
studs and outer walls from fire.
But you have a point, there really isn't much
reason to not put up drywall, unless you really
have run out of money.
I'm with you there. An additional reason to cover it with something is
looks. My BIL in B.C. did his with just insulation+visqueen (clear
plastic). Nice and warm but it looked very red-neckish. He covered it
after a few years. The storage space bit alone is worth whatever cost
the covering would be.
I'd go with either covering it with drywall or not installing
insulation at all. IMO, leaving it uncovered, it will be too easy to
damage. I'd also consider if the whole thing is worth it from an
energy standpoint. Apparently there is no living space above the
unheated garage and the garage only shares one wall with the house?
You can't insulate the overhead doors beyond what they already are,
which likely isn't a lot. So, I doubt doing the other walls is going
to gain you very much.
Agreed - no point in having poly over the insulation if you know it'll get
holes in short order.
I've got a fully insulated (but not heated) garage, and I think it's definitely
It gets to -30C around here in the middle of winter, and the coldest the garage
is -9C. At that temperature, it isn't necessary to plug in vehicle block
saves quite a bit of money. It's also a lot more comfortable in there.
Actually, it is possible to insulate an overhead garage door (I have a friend
done it) but it'll look very 'ghetto'. My friend basically took some fiberglass
couple of layers of heavy-duty poly, and some duct tape and strapped everything
:"I've got a fully insulated (but not heated) garage, and I think it's
definitely worth it.
It gets to -30C around here in the middle of winter, and the coldest
the garage drops to
is -9C. "
The real question here is what would the temperature inside the garage
be if there were no insulation. It might not be much different with or
without the insulation. When you have one side already insulated and
shared with the house, one wall mostly doors which we agree generally
don't have much insulation, you're left with two walls that you can
work with. I suppose one benefit could be that insulation would
reduce drafts from the open walls, especially if drywalled over and
that might even be the biggest factor.
Whoa. Of course it would be much different unless
your garage door has holes in it. Insulation of
the two walls that are part of the house, reduce
flow of heat to the garage. Insulating the two
walls not against the house reduce heat flow from
My garage is insulated all around, but the door
isn't insulated and it doesn't fit tight.
Temperature in the garage is usually in the 50's
when the outside temperature is in the low 30's.
It has never frozen in my garage, but came real
close when outside temperatures dropped further
than -10F. I plugged inflow around the door with
old socks and towels at that time. So figure
20-40 degrees higher with insulated walls. Oh,
and an insulated ceiling.
==============My one garage houses 2 "summer" cars....they are stored over the
winter...and on the second floor of this garage is my
woodshop....which means I have this building heated as I practically
live out there in the winter...and I do not use the cars...
The 2 regular sized garage doors were a major source of heat loss
UNTIL I picked up a couple of "used" hot tub covers for free a few
years ago... now I just unfold the hot tub covers and cover the doors
on the outside of the garage... Honestly it cut my heating bills big
time... cost was about 10 bucks for hardware to hold the covers in
place.... and to be honest it really looks pretty good...not tacky
Done all the time when people are short of funds.
Safe? you expect the fiberglass to burn?
But why not put up drywall which will protect the
vapor barrier from being torn. It's not that
expensive, and you don't have to tape if you don't
Actually, the reason I was trying to avoid the drywall was simply that
I have no experience in putting it up. I figured the insulation
couldn't be too hard, but the drywall I could screw up.
or security reason to put up the drywall... Everyone seems to agree
that I should, which I probably will, but is there a building code rule
of some sort around it or does it make a difference in terms of
temperature inside the garage with/without the drywall?
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