Our first 4 chicks are almost 6 weeks old and the coop is almost finished. I haven't made the chicken door yet... does anyone have a suggestion on how high to make the door off the ground? If it is higher up is it safer for our chickens? At what height should I include a ramp? We live in KY so it is not super hot in the summer and not super cold in the winter. From what I've read 10-12" X 10-12" seems to be about the right size. Thank you in advance for your help with these beginner questions.