taping a celing?

i have just put up my ceiling and it looks good for a first attempt. question,
how do i fill the joins at the end of the plasterboards where there is no taipered ends? thanks.

I assume you’re having the cieling plastered? If not you should have used tapered edge boards!

The joints are taped with either a modern, self-adhesive fibre glass reinforcing tape or original jute tape. It’s usual to use square edge boards if the whole ceiling is being plastered & the tape is covered by the plaster skim. If not plastering the whole ceiling, use taper edge boards & the joint/tape is filled/skimmed out level to hide the tape (never looks good in my view). You can’t just use caulk or flexible filler; if you don’t use joint tape it will ALWAYS crack open again.

i did use tapered edge boards but they are only tapered along the lenth of the board, not the width.

Silly me didn’t think of that! It’s more usual to see taper edge used in a commercial environment than domestic & then for stud walls, not usually ceilings. As far as I know ceilings are always boarded with square edge, taped & skimmed; this hides the joint tape. You could try taping skimming locally to blend into the surrounding area around 200-250mm each side. I use this method very successfully all the time to repair cracks in existing plaster ceilings but I’ve never tried blending into raw plasterboard before; I reckon you will always see it through the paint as you will the local skim over the board tapers. Why don’t you get the whole ceiling skimmed, it’ll look so much better & be worth it in the long run.