I am a newbee so forgive me if this is a dumb question but.. Why do I need a coop door? The coop & run I built is screened in with porch screen and chicken wire. Why do I need to lock the chickens in the coop if the run is secure?
Only hardware cloth will keep out predators. (And it would also need to be buried or aproned out along the edges, and the pen covered in it too.) Weasels and rats can get in unless it is 1/2" hardware cloth.
That would be a Fort Knox run. So, rather than spending all that money for the perfect run, people choose to close the chickens up at night. A raccoon can open chicken wire with it's "hands" quite easily, and dogs can tear through it.
Some people say that there IS no predator proof run, and the wild animals spend all night for HOURS searching for a way in. One person wrote on BYC that he or she saw raccoons tearing off roofing shingles to try to get in a coop. They can open latches the same as a toddler.
It is cheaper and easier to close chickens up in a wooden coop with the windows done up in hardware cloth for most people.
These are things that I have noticed while reading lots of posts on BYC.
I have my coop inside a Ft Knox reinforced run. I often just don't close the door if the weather isn't too cold/rainy/windy. The girls like to get out much earlier than I like to wake up and let them out. I do weekly checks around the whole run, though, to look for evidence of any weakness or attempted break-ins.
Porch screen and chickenwire isn't a secure run, sorry. A solid sided coop with a securely locked door will keep your chickens safe if a raccoon comes by at night and rips into this run (which it could easily do).
Even a fluffy rabbit can get through screen wire. And chicken wire is barely able to contain a chicken. Hardware cloth...the only predator proof wire. Unless of course you have bears...nothing short of a shotgun stops them.
Your run certainly is not even remotely secure, a raccoon would go thru it in about two and a half seconds and so would any number of other predators.
And frankly even people with much more securely-built runs, who are CERTAIN that their welded wire and hardwarecloth and all that will keep out all comers, not-infrequently wake up one morning to discover they were mistaken <insert bloody pile of feathers here>
You need a coop door with your current run, and you would greatly benefit from one even if you significantly beef up your run fencing.