I've got a small side job lined up to paint a kitchen ceiling. It is in real good condition but I was wondering if I need to just clean the ceiling or prime it first. I'm thinking that over the years there might be some grease from the stove, etc. It doesn't appear so however. I thought about using TSP (trisodium phosphate), a heavy duty paint cleaner, then just apply new semi-gloss paint. My other thought is to use a Kilz (sp?) product to prime the ceiling then paint. Thoughts, suggestions? Of course I could clean the ceiling, then prime, then paint, but I don't know if that is really necessary, and if the customer wants to put that much $$$$ into the job. Thanks in advance for your reply.