what coating does the ceiling have...sealer/stain/topcoat....a combination? I've used deglosser to older surfaces w sheen...then painted without an additional primer step. It worked well...getting newer paint that has priming/painting in one step may be your key to this. But you have to assess what is the top coat on that ceiling surface that you are trying to get the paint to adhere to. What is the age of it? You might be well served by hiring someone. Ceiling surfaces are so much more easily dealt with by those who do them regularly....not that you can't...but use your valuable time elsewhere is my best advice.

This had to be used in my DD's study and her son also has asthma. We waited to do this until they were out of town on spring break. Even then, we left windows open as we were concerned about the fumes harming their cats. BIN is powerful stuff and the smell is horrible! But it works!