Not sure where this goes, lighting in coop?

I'm in NC, we do get some chilly weather at night (and sometimes day) during the winter, but nothing like up north. I'm in a lower portion of NC, Union County area. I'm trying to figure out if my chickens will be ok without lighting during the winter or not. My coop has 2 windows on it (with screen), but they're the main source of ventilation right now (there is a SMALL amount of ventilation at the bottom of the coop). I think I need to add more ventilation at some point for winter, not too sure though. The windows have been great so far, but this will be my first winter, so I'm trying to get ahead of the game and figure out what, if anything, I need to do.

Here's a picture of my setup, not sure if you can see in the picture or not, but at the back wall behind where the door is there's a window there the same size as what's on the front (which I actually closed part of the way so the wind isn't getting in with the weather we've been having, it's open, but not all the way right now). On the bottom of the coop I left a small gap where I put chicken wire for ventilation, so the metal siding doesn't go down to the ground around most of the coop). The door also has a screen, and a window on it (which needs to be repaired). I'm not finished with the coop, but it's functional, which I had to focus on first, so there's still more work to do that I've been working on as I can afford/have time to:

They don't "need" lighting, they will be just fine without it. Folks will add lighting in winter to force the hens to lay more eggs. We have tried it for a couple years, but this year are going to go without extra lighting (we're up near the Canadian border). The lighting is unnatural and somewhat hard on the birds, but some folks swear by it for more eggs. At our northern latitude, folks say you want to start the extra lighting on or before mid-September. Already we are into October and we are still getting 4-7 eggs a day from 11 hens. We will see how it goes this winter and in any case, you are supposed to give them a break from the lighting every couple years. Some breeds lay better in winter than others, even without extra lighting. I know one lady who got 4-5 eggs (each per week) from one of her breeds (without extra lighting), sorry that I don't remember which one.

I do agree you should put more ventilation in your coop. There are some great articles here in BYC about ventilation, but the nutshell version is to put your vents low near the ground AND up high near the roof AND in such a manner than cold air does not blow directly on the birds. So if the roof of your coop is just a foot above your roosts, then you should lower your roosts at least 18". Also, most frostbite issues come from not too much cold, but too much damp air. Putting more vents (more than you think you need) will help move out the moist air from the birds' breathing and keep it drier in the coop.

Also, I would not recommend messing with adding heat to your coop. They don't need it, unless they are not cold-hearty breeds (most common breeds are cold-tolerant) OR you live in True Cold, like the Arctic. I know folks in Alaska that do use heat in their coops, but it is not set to kick on until the temps have dropped to -20F. For most everyone else, the risks are just too great to add heat. There are lots of very sad stories here on BYC of coop fires from heating issues where all the birds burned to death. Chickens will keep themselves warm by 1) Having a dry, well-ventilated coop that does not allow drafts to blow directly on their bodies, 2) A well-balanced diet, 3) Fluffing their feathers out to increase their insulation and 4) Huddling together as a group at night to keep warmth together.

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I will have to measure how low the top shelf is. The building is 6ft tall. and the top shelf is mounted to one of the back wall bracing 2x4s that I think is about 1/3 of the way down. The bottom shelf is definitely low enough for them to be on.

I have venting all the way around on the ground of it (I left a gap where I used chicken wire for ground ventilation), but I'll have to see if it's enough down low. With the heat of the summer it never felt stifling hot and it didn't have too strong of a poop or ammonia smell.

I don't see it getting that cold. The coldest I remember in the almost 15yrs I've lived here was one winter we had teens because we had a terrible ice storm come through.

The humidity, I live in a pretty humid area, but usually during the winter is when we get a break from the humidity to a point. I'm going to take the tips and when I go out to do some improvements I'm going to see where I can make them I'll have to look into appropriate vent systems where hornets/wasps etc can't build a nest in them though.