Walls and Ceilings - Ceiling Drywall

Can someone explain the logic of using 5/8 drywall for ceilings instead of 1/2 inch? Seems to me that it just adds more cost and weight, and 1/2 inch works just fine.

5/8" rock is stiffer and will give a flatter ceiling. 1/2" gives more and is apt to show waves in the ceiling due to irregularities in the ceiling rafters.

is 24" o/c i.e. a truss, then you will notice the difference between 5/8" and 1/2". If the framing is 16" o/c or less you won't notice as big a difference.

5/8" is a waste. You only need 1/2" for walls and ceilings for typical home construction applications. The only time you may need to consider 5/8" is if there is a building code regulation requiring a thicker surface, i.e. fire separation.

Install 1x4 on the under side of the joists every 16" which allows for easy installation of the drywall. A larger spacing would promote sagging.

My basement ceiling was done in 1/2" and it is flawless.

Cheaper to use 5/8" rock than to install strapping. :)

1/2" drywall will eventually sag if there is going to be insulation blown in on top of it, 5/8" drywall will not. It may not sag right away, but the weight and humidity will take its toll. If there will not be any insulation, 1/2" drywall usually works, even on 24" centers, but 5/8" is definately recommended for ceilings, and I would hazzard to say that every contractor knows this. Homeowners might be tempted to cut corners. Contractors would rather avoid call-backs.

Then again, every once in a while you get the contractor that doesn't have a drywall lift, and wants to save his back. He'll vote for 1/2" too.

I used to paint for a builder that built high end homes and used 1/2" rock on the ceilings with a slick finish. DIDN'T MAKE IT RIGHT THOUGH.