I am a new at home improvement and need a answer to a question about painting a primer, first coat on a sub-floor that is not wood nor concrete. The sub-floor looks a dry wall but much stronger. I found a gallon of latex based semi-gloss enamel paint. It is a light pale yellow color. Could I use this paint for a single primer before putting a darker slate blue floor enamel over it as the finished project? This is for a bedroom floor that will have a large area rug covering all my mistakes. lol I have searched the internet but not found an answer do to the now worldly craze for wooden floors. If I wanted to pain a wooden or concrete floor to look like a wooden floor I would have lots of answers and opinions on how to do it, but alas, my simple answer must be out there among you home improvement experts. Can you help I want to start painting soon??