Hi all,
I’m preparing to insulate and drywall the small upstairs room seen in the attached photo, converting it into a storage space. The rafters are full 2×4’s set roughly 24″ O.C. Will 1/2″ drywall on the ceiling sag, and if so, is that a structural problem, or just aesthetic? The room will only be used for storage, so the sight of sagging drywall won’t bother me unless it will end up falling down or otherwise creating structural problems.
Thanks for any advice.
Kyle
Replies
Where exactly is this space? Is their any insulation being planned? Are you just looking to keep stored items cleaner?
I would look at using the fiberglass faced DenseArmor drywall. It's a little harder than standard, and it doesn't absorb moisture like paper faced does - that would be my only concern. You can use 1/2" as long as you are going across the rafters, not parallel.
Thanks for the reply, Paul. I'll put fiberglass bats in the ceiling so it will be a conditioned space.
I'll second the recommendation to use fiberglass-faced drywall. Much more durable.
Whats your adversion to 5/8"?
Whats your adversion to 5/8"? 1/2" drywall is rated to span 24" but in practice it just doesn't work well. It will sag and could easily cause you an inspection report problem should you try to sell the house down the road. The primary factor in determining whether or not you will get drywall to sag is the amount of humidity in your region, and the area of the home your installing in.
They do make 1/2 " drywall made specifically to span 24" (I think the stuff was called span-24, but I haven't worked for the builder that used the stuff in years.). They also make fiberglass reenforced drywall that uses a more dense core that would work well, this is the dense armor mentioned above. It's great stuff and works well in almost any situation. The only problem here would be the added expense. In addition DenseArmor is quite a bit more heavy and the fiberglass backing tends to make your arms itch and such after working with it all day.
I think once you look at all your options you'll likely go ahead with the 5/8", even though you might be able to squeeze by with 1/2" as long as the space stays air conditioned all the time. If it's worth doing, it's worth doing right. Good luck in your project.
Hi Robert,
Thanks for the reply. When I first made the post, I thought I had enough 1/2" from a previous job to do the walls and ceiling, but I have since realized I will need to buy more drywall for the ceiling, so 5/8" makes sense to me in that case. My only aversion to 5/8 is the weight during installation, but I guess I'll survive!
Thanks again!
But if it is plywood over skip sheathing then there's a lot of leakage out the edges, etc, and if the ceiling is covered reasonably well (with taped seams and a coat of paint that's perm rated) then there shouldn't be any problem with moisture up there (at least not coming from the inside).
I've lived both places, and Kentucky ain't Minnesota -- temps much below freezing are rare. Thirty degrees and drizzle is the standard winter weather.
Will the sight of mildew and mold bother you? How about the smell? You had better get used to it if you plan on isulating and rocking your attic. I live in Tennessee, not to far from you. We have very similar climates and crazy high humidity. If its just storage, why the sheet rock?
Cathedral ceilings are dangerous around here. I suppose if you spray foamed the underside of the roof deck before the sheetrock you might get away with it. Can you get R-40 with spray foam out of a 2x6 rafter? I'm pretty sure you can't with fiberglass. PaulC was right on the money. Ventilation is crucial, especially around here. If it aint broke, dont fix it.
I would hope he would give up on getting R40. Just shove in some R15. There's nothing there now, so anything is an improvement, and this is not intended to be inhabited space.
Yeah, my brother did the exact same thing at my Mom's house. Have at it.