trimming t&g at ridge

rtoni

hi all - looking for advice. I have a t&g pine vaulted ceiling, approx 30' ridge / gable ends. Short collar ties are right under the ridge and these may be covered in same t&g material. The collar ties are for code / uplift, and I have rafter ties down below (top plate) which will be boxed in later.

The transition from sloped ceiling to the horizontal plane (collar ties) is where I'm focused. Not sure if I should:
1) bevel the top ceiling board edges (plumb), and butt the edges of the horizontal boards against that?
2) bevel the outside edge of the horizontal boards (angled to the ceiling plane), to cover / hide the top edge of the ceiling boards?
3) scribe anything?
4) just use trim?

Worried that option 1 or 2 may leave a gap if the wood shrinks a bit (which I think is likely when the dry winter air hits), or anywhere that the boards aren't butting together "perfectly" along the transition

Scribing - I would probably waste a lot of material trying to do this.

Trim seems like my best bet from a stay out of trouble perspective (although this may cause some of you carpenters out there to cringe a bit). Maybe some 1x2 or similar at the transition? Possibly rip / bevel some kind of stock trim to make a nicer looking job? I'm just spit-balling - any suggestions on how to do this would be very much appreciated.

joecaption

Post a picture.

DannyT

i would bevel the new boards to fit the existing. gaps in wood from summer to winter is a fact that you can't change. if they are butted tightly in the winter in the summer when they swell you could have bigger problems then a few small cracks. anyone with hardwood floors
knows that te joints open a little in the winter and close in the summer. now if you can bevel the top edge of the existing and let the new boards overlap the existing then you won.t have a there but between the others there is always a chance you will have small gaps when the humidity is low. ripping a piece of trim to the corresponding angles and nailing it in the corner would work also

Duckweather

If you bevel the horizontal boards first to the angle of the rafters, and bevel the rafter boards to the angle, (plus a degree or two), of the horizontal boards, called shiplap. When they shrink the joint slides a little and is harder to see looking up at it.