Plasterboard orientation vaulted ceiling

[junglejim]

I’m building up my ceiling layers. I have insulation between rafters, then internal osb, then super quilt heels in place with vertical battens screwed through to rafters. I’m then counter battening (horizontally) to create a 50mm void for downlighting and wiring etc. because it’s a vaulted ceiling I’ll need to lay plasterboard ‘landscape’ so the length will follow the same direction as the horizontal battens. I’m wondering if this is ok? I’ve read that plasterboard is designed to be installed with battens perpendicular to the length. I figure if the spacing is smaller it’ll be ok but looking for advice.

 Thanks

[Redbeard]

The bound (long) edge helps to prevent 'droop' but I doubt you'd have serious problems on an un-bound short edge. 1800 x 900 or 1200 x 2400? I always used the former since I did a lot of attics solo and am too much of a wimp to wrangle 1200 x 2400's above my head.

[Kelvin]

I did landscape. Easier to mange the boards too. 

[Oz07]

Surely you want them perpendicular?

[Nickfromwales]

Depends on the spacing of the battens. 
 

At 600 oc you want then perpendicular, but at 400 oc you can go landscape without any issue.