Too thin sparse panel for plastered ceiling?

[steffner]

Hi,

I have started the sparse framing of the ceiling to later be able to install drywall and am now wondering if it might be too weak for the heavy drywall ceiling. I don't want a sagging ceiling or other issues in the future.

Info:
The house was built in the 50s.
The roof trusses are cc120 and the underlayment is of raw wood planks 22mm.
Under this, I have furred with 22x70 for electrical conduit and then sparsely framed with raw boards 22x70 with cc30. I plan to use 90x240 drywall.

I know (now) that the standard is 28x70 with cc30 but to save ceiling height, I would like to keep the 22x70 if possible.

What do you think, is it okay or should I switch to 28x70?

Regards

 

[gadu^]

Does 6mm matter in ceiling height?
Granted, 22x70 works well too...

 

[steffner]

Sure, 6mm is not much, but if you add up all these small "savings" it becomes a significant amount.

 

[Beppo]

Hello,

I have started spacing the inner ceiling to later install plaster and now wonder if it might be too weak for the heavy plaster ceiling. I don't want a drooping ceiling or other trouble in the future.

Info:
The house was built in the 50s.
The roof trusses are cc120 and the sub-ceiling is made of 22mm tongue and groove.
Under this, I have lined with 22x70 for electrical installations, then spaced with rough planed 22x70 with cc30. I plan to use 90x240 plaster.


I know (now) that the norm is 28x70 with cc30 but to save ceiling height I would like to keep 22x70 if possible.

What do you think, is it ok or should I switch to 28x70?

Best regards

The easiest would have been to space with 28/70 against the tongue and groove and run the electrical in the spacing, saving 16mm in ceiling height. The thing is, it doesn't matter if you have 22 or 28 at the moment since it sits in the lining which is 22/70. It is still the one that has to carry the whole ceiling. But since it's against tongue and groove, if you have nailed it properly, you can put 28/70 against the lining and you’re good to go. However, you'll be 6mm poorer.

 

[steffner]

The 22-glesen is screwed into two rooms, so I would prefer not to tear it down and use 28.

I can add that I placed blocks between the rafters against the raw boards for reinforcement.

The salning with 22mm is screwed across the rafters, so it doesn’t negatively affect the durability. I want the salning because there will be a crazy amount of pipes in the ceiling, which would turn the glesen into a sweicherost.