 I think acrylic primer is fine in this case, but you can't just put ceiling paint on it because if you do, the stain will sort of draw right through. You've got to prime the spot first and then paint over it, and you should be good to go. All right. Now, Jan wrote in wanting to know how to tell the age of a home. She says, I've heard you ask listeners how old their house is, and I'm wondering how I might figure that out for my house.