Let me add to the comfort/cold floor issue: If you are going to put down some kind of flooring anyway: Look at radiant heating possibilities! Lowe's has an electric mat (I am not home so I don't have info) that we installed ourselves that is heavenly! It has a thermostat and heats in minutes. We keep it on all winter in our bathroom and the electric bill did not even register a blip , but electricity is still relatively cheap in VA (for a short while anyhow). The mats come in different sizes and you can connect as many as you need. I would not do the whole room, only where my machine was going to be. You aren't trying to heat the room - just your tootsies!
http://www.suntouch.com/diy/