I am getting ready to install insulation in my attached garage crawlspace above drywall that is already installed in the ceiling. The garage is not heated and the 2x4 trusses are on 24 inch centers. Do I still need Faced insulation for this application, or would Unfaced work? I am in Northeastern PA, so we do get pretty cold winters. I already have the exterior facing walls insulated with R-15 Faced. Thanks in advance.
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Insulating unheated attached garage ceiling - Faced or Unfaced?
- Thread starter kdrymer
- Start date
mike93lx
ALLIANCE MEMBER
Vapor barrier goes to the warm side. There must be something adding warmth or this is no reason to insulate.
billconner
Well-known member
it won't matter a lot but the vapor barrier function of the Kraft paper will be compromised some by not being fastened to the trusses. Unfaced fibreglass or blown in cellulose (my preference) and a vapor barrier paint on drywall would be a little more effective IMHO.
rayra
Well-known member
Pretty sure the OP was talking about an attic space above, rather than a crawlspace under.
The painted drywall is vapor barrier enough. Just get unfaced 24" batts and call it done. Go for at least R19 and maybe even R38, running a second layer of R19 crossways, if you can afford it.
The painted drywall is vapor barrier enough. Just get unfaced 24" batts and call it done. Go for at least R19 and maybe even R38, running a second layer of R19 crossways, if you can afford it.
To meet energy ratings here (and it's SOP) 6 mil plastic goes between the studs and drywall as a vapor barrier. I've never heard of paint being able to act as that.Pretty sure the OP was talking about an attic space above, rather than a crawlspace under.
The painted drywall is vapor barrier enough. Just get unfaced 24" batts and call it done. Go for at least R19 and maybe even R38, running a second layer of R19 crossways, if you can afford it.
That being said, probably fine without in a garage, even more so in a temperate climate.
billconner
Well-known member
I wrote vapor barrier paint but should have been vapor retarder paint. I've read of this long ago. Lots of articles (and products) googling.
CombatNinja
Well-known member
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OP, what is the goal here? Just trying to control temps a bit more for part of the year or what? Ultimately, without HVAC insulation will not really do much.
TractorJeff
Well-known member
AH! But maybe he is doing this project in financial steps?OP, what is the goal here? Just trying to control temps a bit more for part of the year or what? Ultimately, without HVAC insulation will not really do much.
Walls are insulated, definitely insulate the ceiling!
Unfaced would be easiest to put in.
If the Kraft paper cannot be sealed, then no reason to use it is also my OPINION.
toolmiser
Well-known member
Somebody will correct me if I am wrong, but I've been told by an "energy consultant" that fiberglass insulation doesn't prevent air movement so something like cellulose insulation will keep the air from flowing out thru the insulation. I would recommend either getting a blower or having someone blow all the insulation in your attic. You will get a better job.
K'ledgeBldr
Well-known member
For an unconditioned garage- insulating the attic will certainly retard heat gain during the summer, and would probably help retain vehicle heat in the winter. But, I certainly wouldn’t over-do the insulation- the ROI isn’t there.
And I certainly wouldn’t have spent the money on the walls- unless there is a possibility of adding heat&air down the road. But why?
And I certainly wouldn’t have spent the money on the walls- unless there is a possibility of adding heat&air down the road. But why?
Mick56
Well-known member
I have a fully insulated, unheated, attached garage in WI., it is usually 20 degrees warmer inside the garage than outside during the winter.
I insulated the walls in my 16x20 shed before sheathing it. Figured it was much easier to do then, vs deciding later and having to pull everything down and rip down OSBI have a fully insulated, unheated, attached garage in WI., it is usually 20 degrees warmer inside the garage than outside during the winter.
jsaw
Well-known member
OP, what is the goal here? Just trying to control temps a bit more for part of the year or what? Ultimately, without HVAC insulation will not really do much.
In the winter my insulated unheated garage will stay above freezing unless the temperature is down around 0 or 10 degrees for longer than a week or so.
CombatNinja
Well-known member
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So you're saying it's 15 degrees in your garage in the winter. Got it.I have a fully insulated, unheated, attached garage in WI., it is usually 20 degrees warmer inside the garage than outside during the winter.