I have a old hard wood floor that isn't level in spots. Almost like the boards swollen so much they are buckling. This is going to be my 3 year old and 1 year olds play room. If I sand the whole floor and get the high spots out. Do I need to stain and poly if I put a new floating floor on top? What type of flooring would you suggest considering this is a kids play room. The reason why I want to cover the old floor is because between the new walls I put up and old floors. I have a 2.5 inch gap in the floor. So base boards won't cover the gap. I could see critters crawling in or the kids dropping toys under the house in the future. Thank you so much for your time and advice. via /r/DIY http://bit.ly/2SfXGER
