I have a plaster ceiling. The contractor wants to rip it out to install dry wall. And I want to put tongue and groove pine on the existing ceiling.
Go with tongue and grove with a nice stain. It will look gorgeous!
If you remove the plaster, you now have a fresh slate for the future. You now have access to insulate for either noise barrier or simple r value. Also if you find any defects within the ceiling, you can properly fix them and then you can still add t&g pine
You can install the t & g over the plaster as long as you nail them into the ceiling joists.
If you have sufficient insulation in the attic, you’re okay. If you live in a cold climate, make sure heated indoor air cannot enter into the cold attic space and cause condensation to form on any wood framing etc. You can also call your local building dept. for info. and advice. Additionally, there are many online sources you can look at.
Budget could play a role in your choice. The construction of your home could also make a difference in if the drywall has to be removed or if the T&G can be put over it.