Re: I am painting my bathroom and the paint is bubbling, Why?
My suspicion is that you did not get good adhesion to the paint you were going over and that you should perhaps have primed the walls for the sake of adhesion before painting.
It also sounds to me like you didn't do much prep work prior to painting. Wiping the walls down with a rag and some warm mildly soapy water to remove anything that shouldn't be there. Things like hairspray, aerosol air fresheners, finger prints can collect on the walls over the years. During this step you might have noticed some of the old paint starting to fail. A quick scuff before you painted or primed would also have alerted you as to any fractures or peeling on the original coat.
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