Insulating a Garage question

[RJ Schuff]

Not so stealth gloat advisory. :p

For my 50th birthday I decided not to act my age an bought a 2003 Dream PT Cruiser, Series 2. Now I want to heat and insulate my garage so I can clean it and stare at it during the cold winter months. Sheesh.

I am all set with the heater portion of the project. I am having installed a Modine Hot Dawg 75,000 BTU natural gas heater next week. My question has to do with insulating the garage. I have never done this and am wondering what particulars I need to know. It seems the spaces between the studs are much narrower than the 16 inches on center I am used to in the house. Do they make insulation that is a garage width or am I going to have to cut bats? Any recommendations on specific products would be helpful. What about vapor barriers? I do not plan to keep the garage continually heated, just when I want to be out there. It is a 2 and 1/2 car garage that is unattached to the house.

I was thinking about sheathing it with OSB, but after reading the thread about current prices I think not. How about Drywall or pehaps nothing at all but plastic?

Any advice would be appreciated.

RJ

[Perry Schmidt]

All the garages that I've insulated have standard studs - 16" OC. So not sure what you got. If it's not standard, I would just cut down the bats or squeeze them in - depending on how far off they are. And use a vapor barrier.

RE: sheeting, my dad did the same thing for same reason...different car though. He used sheetrock, but then put plywood on the bottom 2' of the wall to resist water, prevent damage from water splashing, snowblower bumping into the walls, etc. Works very well. Don't need to go any higher than that, but the lower 16-24" needs something more durable than sheet rock.

Perry

[Lee Schierer]

Looks like you ewill need to cut strips of insulation for those narrow place. Don't squeeze it in as that greatly decreases thei insulation value.

Are you sure you need 75,000 BTU's to heat a 2-1/2 car garage?? I heat my entire house in NW PA with a 50,000 BTU furnace and it heats 2400 square feet. Don' t know who advised you on such a large unit, but it seems like over kill to me.

[Perry Schmidt]

RE: 'squeezing them in'. Well I do agree you don't want to really squeeze them in if you have - e.g 6" less space. But if it's only and inch, I would squeeze it in. Not optimial but cutting an inch of the length of a bat isn't always the easiest thing to do. And too many times I've seen it cut too much. Then the bat doesn't have enough friction to keep it up, and over the years it will sink. I've taken apart walls where the bats have sank and a good 1'-2' on the top there's no insulation - nothing but dead air.

So like I said - depends how much you'd have to trim off. 1" I wouldn't. 6" I would. In between, all depends on how accurate and straight you can trim the length of a bat. I'd cut some off probably, but error on the side of 'too fat' than 'too little'.

(Of course using paper backed bats helps the 'sinking bats' problem. But I presonally don't like paper backed bats. Just a personal preference.)

Perry

[Jim Becker]

If you have a lot of non-standard spacing, it will be easiest to insulate with un-faced batts and then use a poly vapor barrier. That all must bee covered with drywall or some other material...fire hazard otherwise. Perry's idea for drywall on the whole thing followed by something more durable on the bottom half has merit.

[Wes Bischel]

Well, I hope your studs are 16" OC, otherwise, cutting them down is a pain - lots of little ones ;) A tip on cutting - use a 2x4 to compress the batt and use it as a straight edge. I can usually cut with one pass using a sharp utility knife. The fewer slices, the fewer fibers floating around.
I would concur on the unfaced with a vapor barrier if the width needs to be cut - then all closed up with drywall. I like the idea of the plywood on the bottom, unfortunately, code in my area required 5/8 type X for fire rating even on a detached garage.
Nice score on the Cruiser!

Wes

PS - when working with fiberglass the usual safety precautions apply - and when done - take a cold shower first. Keeps the fibers from getting into your pores.