They need a way to get in and out on the mornings and nights I am not able to get out there. Currently they only have a standard door that we've been opening and closing for them. But we're going away for a few nights next month and trying to figure out the best method.
Just cut a pop door hole in the "human" door. It'll be fine with your set up and then the chickens can come and go as they please. It'll also add a little low ventilation. If you want to add a slider or hinged cover as described in post #5 you could do that, too.