I have a 1900 house that's never been insulated, and I'm putting in a new bathroom and kitchen. I plan to blow in cellulose insulation in most of the house walls.
In the bathroom, I have a small space that is 9' above the shower. The ceiling is lath and plaster, but I want to install cedar tongue & groove on top of it. I already put an exhaust fan and recessed light up there. Because it is boxed in by a large beam, I am concerned about moisture build up. I am going to put a vapor barrier in the whole bathroom ceiling. Above the tub is the only space with lath and plaster.
Can I simply staple the vapor barrier to the plaster? Then nail the cedar on top of that? It would be a hassle to remove the lath and plaster just to install a vapor barrier.