Sheetrock a Garage Non-vented, No insulation, Gambrel Roof?

[dKirkwood]

Hi,
I am a homeowner. I have a 2 story detached garage, built about 100 years ago. The second floor is a nice space (20x20); the roof is gambrel, with no walls; it is 2x4 rafter construction, 12" centers. It is not vented--either on the roof ridge, or at gable ends. I want to use the space as a shop area, and I don't intend to heat it. It is fine with me if it is freezing cold in winter (I live in New York city area).

So, I would like to sheetrock the interior, mainly to paint it white, and improve the lighting. I don't want to insulate, to save the money, since I don't want to heat. So, my question is, will putting sheetrock on such a system cause condensation problems? Putting sheet rock on will effectively seal the cavity between the rafters; so that is what I am wondering about--is that a problem?

If so, I was thinking of leaving a 1" gap at the bottom of the sheet rock, where the rafters connect to the wall headers--and leave a 1" cab where the sheetrock meets the curb assembly (I think that is what you call it--it is a double 2x4 girder that forms the joint between the rafter run from the floor to the curb, then a new shorter rafter runs from the cub to the roof ridge) -- So that gap would vent the first, floor-to-curb rafter bay--then do the same on the short rafter run--leaving a gap at both ends to facilitate air movement. I could then install 2 gable vents on each end.

So, would just sheetrocking, with no gaps be ok, or should I leave the gaps and install gable vents?

Thanks for help--it seems impossible to find answer to this question, as all information is about insulating--I don't want to insulate.

 

[Irv]

You man not get many answers, because, frankly, it seems, to be polite, "not very smart" to do all that work and not insulate. Insulation isn't very expensive, so why not be more comfortable?

There's also another factor that may someday be important to you. If I were buying a house, and the garage was sheetrocked without insulation, I'd wonder what other corners were cut in the building/remodeling.

Unless you've taken some kind of religious vow of suffering, why not do it right?

 

[dKirkwood]

well, it might not seem very smart, but, if you appreciate the implications of the structure not having any venting at all, putting in insulation would, in fact, not be terribly smart, because it would almost certainly result in condensation problems, and associated issues like mold, and rot on the sheathing.

And, if one understands the difference between vented/non vented structures, one would understand why there could be an issue with the same complications simply by installing sheet rock, even without insulation.

It is true, there are methods one could employ for this situation to get insulation in--put those methods are quite costly. Were the extra cost to install insulation a few hundred--as would be the case if the structure were vented, and all one had to do was slam some fiberglass in there, I'd agree, it makes sense to insulate, and it doesn't make much sense not to.

But, insulating a non vented structure of this size correctly costs several thousand, not hundreds. So, for the use I have in mind, it is not cost effective to spend the extra thousands.

If, people won't answer the question I have, I suspect it is more likely due to folks not understanding the difference between vented and non vented structures, as well as the complications a gambrel structure brings to venting the structure as it applies to insulation installation