I have constructed an 8' x 16' coop. 8' tall at front and 6' at back. Basic slant roof design. I have a standard steel entry door for humans with two 3' x 3' storm windows with screens for partial ventilation and sunlight. The run is 16'x40'. I have yet to construct doors for the chicks to run to and from the coop. I would like the chicks to have a free choice to enter and exit coop at their own convenience throughout the day. Predators are going to be a problem after dark even though the chicks are in a non roofed 4' high fenced run area attached to the coop. I see lots of pictures on BYC showing cut out chick coop entries, but no door construction ideas for closure or latching shut at night. Does anyone out there have any suggestions or pictures that work for them?