Since it is going to be in a bathroom I would primer it with Kilz as they have one that helps prevent mold and mildew from popping up on the walls. My house is 90 yrs old and the br was made out of part of the original kitchen as there wasn't running water here when they built the house. Ventilation is a problem with the bathroom so when we remodeled we used this to help prevent the mold and so far it is working. Before this we had problems every few years.