I just purchased a 12 year old 2-story home in Oct 2011. Since moving in the home we hear lots of creaking in the floors on both ou main floor and upstairs - even when no one is walking around. We really notice it most in my daughters room and the hallway outside her room. I am worried this could be a safety issue and I don't know what to do. What options do I have or is this normal and I am worried for no reason?