5/8" vs 1/2" drywall on ceiling?

[KBDesigns]

I'm working on replacing the ceiling in the dining room in a house built in the 1860s. The room is 20 ft long and 11 ft wide. The original plaster and lathe ceiling was removed. Because the 2x10 joists (they are literally that dimension because they are old rough cut) run the length of the room, they sagged in the middle of the room. I sistered on a series of new 8 ft 2x4s to each one to level the ceiling joists. The joists are spaced approximately 16" apart, each 20 ft long.

A YouTube video suggested using 5x8" drywall on ceilings, so I installed 5 sheets of 5/8", each 4 ft x 12 ft. Recently, I have become concerned that there is too much weight up there on the ceiling and it will sag again in the years ahead.

Here's my question:
Should I take the 5/8" drywall down and replace it with 1/2" ultra-light drywall?

I looked around online and it seems that there is about a 40 pound difference per sheet. (5/8" 4x12 standard drywall = 105 pounds) (1/2" 4x12 lightweight drywall = 58 pounds) So, using 5 sheets, that's a total of 525 pounds that's hanging up there now. It would be 290 pounds if I replace it with five thinner lightweight drywall sheets.

Is it worth the time and money in the long run to redo it now?

It would be great to hear about your thoughts and experiences.

Thanks

 

[bud16415]

First off welcome to the forum.



I would have likely used .5” and leveled with 1x3 strips, but now that it is up there is no way I would take it down and start over.



If you are worried about the weight I would be looking at the screw pattern you used to hang it and maybe adding more screws if anything. How close did you space the screws?

 

[KBDesigns]

Thanks so much for the speedy reply. We used a LOT of screws, spaced 6" to 8" apart. Here are some photos.

I looked online and found a site that said plaster and lath at 1/2" thick weighs about 10 pounds per square foot. 5/8" drywall weighs about a quarter of that, 2.2 pounds per square foot. So, I should be okay with being so much less overall. Agreed?

 

[Sparky617]

You'll be fine with the thicker drywall. Not needed, but I certainly wouldn't pull it down. Some will argue to only use 5/8" for ceilings, but I've never had a problem with sagging with 16" spacing.

 

[KBDesigns]

Gotcha. Just to clarify, my concern is that the weight of the thicker drywall will pull the ceiling joists down in the years ahead so that the whole ceiling bows toward the floor. The plaster ceiling certainly did that, but it was up there for 150 years.

 

[Krich]

One could also use 1/4 dry wall... that would be even less weight!

No need for a bunch of extra weight when it's not necessary.

1/4 dry wall will look just as good once it's finished out... nobody will be able to look and tell it's 1/4 dry wall as your next dinner party and it's less likely the rafters will come crashing down on your guests!

 

[Sparky617]

Gotcha. Just to clarify, my concern is that the weight of the thicker drywall will pull the ceiling joists down in the years ahead so that the whole ceiling bows toward the floor. The plaster ceiling certainly did that, but it was up there for 150 years.

I doubt it was what was hanging on the joists that caused most of the sag, but time, and what was on top of the joists. Old homes sag overtime.