Thickness of spars with 1038 cc on the beams??

[lillsnickrarn]

We are going to install battens in our sloped ceiling, which will be sprayed with 250mm cellulose. The center-to-center measurements are between 1.20-1.38. Can we use regular battens 28x70 or will it buckle? Should I have 13mm gypsum afterwards or is 6mm enough? We will only have gypsum on the battens in the sloped ceiling. We want to build as minimally as possible for the sake of ceiling height....:blushing:

 

[Mikael_L]

With CC30 between the glesen, I personally wouldn't hesitate to try with regular 28x70-gles.

But I'm not totally sure ...

 

[_bystrom_]

My house has CC120 between the rafters and CC40 for the battens, which has not resulted in any bulges, etc.