Ceiling drywall thickness
 

Hi

I will soon be putting up drywall on ceilings in a 100 year old house. The ceiling joists are 24" o.c. I have heard that I should probably use 5/8" thick drywall (as opposed to 1/2") in order to prevent sagging. Is sagging something I should worry about or can I get away with using 1/2"?

Also, I have heard about a type of drywall called CD board (Controlled Density?) If anyone knows about this stuff and whether it would be suitable for ceilings, I would appreciate any advice. I have heard that it is lighter and easier to hang on ceilings.

Thanks

i used 5/8" fire-x on my dining room addition, and with my handy-dandy homemade drywall lift, it went right up no problem. =o)
they make special 1/2" for ceilings too. i finally posted 'plans' for the lift here if interested.

DM

DM while I was searching for your post http://www.diychatroom.com/f101/can-you-build-your-own-drywall-lift-done-30539/, you came and went, well anyway, I was going to suggest the 5/8, in my area its like 1.40 a sheet more then the half inch, yes its heavier to lift but I figured with your innovative idea it would be alright.

i have to pop on and off.... limited time dialup crap.....

DM

Although 1/2" is acceptable per code in my area, I would go with the 5/8 drywall.

I have seen a few instances of 1/2" over 24" centers with a slight sag between the rafters.

According to local code, 1/2" is acceptable here, but after reading the replies here and doing some research, I will use 5/8" on the ceilings.

I may use CD (Controlled Density) board, since apparently it is lighter and easier to hang. For some of the rooms, it will make more sense for me to use 4' x 10' sheets on the ceilings (less cutting and less taping).

Is there anything I need to know about CD board? I know that compared to standard drywall of the same thickness, it is lighter, but was wondering if there was anything else different about it.

Thanks

they make 1/2" for ceilings that is 'stiffer' so you avoid sagging. but ya gotta ask them for it specifically.

DM

1/2" WILL sag on 24" centers, especially if moisture and extra weight are introduced by texturing; especially if humidity becomes a factor (leaving windows opened in rainy weather). There is a 1/2" "sag-resistant" drywall available (USG.com). You will not find it at the big box stores and it will cost more than regular 1/2" and likely more than 5/8". Contact a drywall supply company for pricing. That said, it may be simpler to just use the 5/8". Or you could "strap" the ceiling with 1"x's on 16" centers to use 1/2" regular. You will likely have to cut every bottom wall sheet if you go that route........

That would be my suggestion as well. Tho, you could go with the 5/8" since the 16" OC strapping will still be spanning 24".

Strap it at 16 centers and STILL use 5/8's.

Why do that?

Better flatter install.