I am in the process of building a new raised coop. It is 2 feet off of the ground. I am thinking of putting my pop door on the floor with my ramp leading down from there. So I have a couple of question for people who have this configuration: 1. Can I leave it open 24/7, or will I have draft problems? 2. If you don't leave it open, how do you open and close it easily? 2. Do any of you use the deep litter method with your door on the floor? If so, how do you keep the litter from falling out? Any pictures would be great. Thanks!!