1) I'm fairly certain I want about 6 hens. How large should my coop (with run) be if this will serve as a nightly 'lock-up' with the potential for leaving them in there over a weekend if I go out of town?
I’m not a believer in magic numbers for chickens in this or anything else. I know you need someplace to start if you don’t have any experience and the 4 and 10 is a pretty good place. It will keep most people out of trouble and is overkill for many. But with different flock dynamics, different management techniques, and different climates, there is no one set of numbers that works for all of us.
I suggest you go as big as you reasonably can. I’ve yet to hear of anyone having problems with too much space, yet this forum of full of problems caused by too little space. If chickens are overcrowded you can have behavioral problems ranging from feather-picking to serious fighting to cannibalism. Commercial operations have proven you can keep chickens permanently in 2 square feet but they take drastic measures like beak trimming to keep them from eating each other. A whole lot of chicken behavioral problems are solved by the weaker chicken running away. They need room to run.
I find if I have more room, I work less hard. Poop management is a good example. I have excess space most of the time in the coop and plenty of outside room. I cleaned my coop out this year for the first time in four years, not because I had to but because I wanted that stuff on my garden. I did have to do some work right under the roosts (they poop a lot while they are on the roosts overnight) but the main coop was no problem.
I find having extra room gives me a lot of flexibility. If I want a broody hen to raise chicks with the flock, she can. If I want to integrate new chickens, I can. I feel that most of the problems we read about on this forum with broodies or integration are caused by a lack of room. If I have a predator problem, I can leave them locked up for days or even weeks while I deal with the problem. If I want to sleep in instead of getting up at the crack of dawn every day of the year to let them out, I can. If the college girl that takes care of them while I go down to see my granddaughter is really late in letting them out, no problem.
When planning your coop, I suggest you consider that most building materials come in 4’ and 8’ dimensions. If you plan around that (and remember to work with out-to-out dimensions, not center-to-center, you can often build a larger coop with no more expense and with less cutting and waste.
I suggest going long more than wide. If you build a wide coop (run too if you cover it) you have to buy more expensive longer and heavier lumber to span the top, especially if you have to worry about snow and ice loads.
Plan on overhang for the roof with lots of ventilation under that overhang. Regardless of your climate, it’s really hard to have too much ventilation in the winter as long as it is over their heads when they are roosting. In a hot climate and during summer for practically all of us, it is hard to have too much ventilation period, no matter where it is. Heat kills a lot more chickens than cold. It has something to do with the down coat they wear.
I’ll give you three articles that I think are really good. I don’t know how important that cold weather one is to you but I think the muddy run and ventilation ones should be required reading for anyone building a coop and run.
Pat’s Big Ol' Ventilation Page
https://www.backyardchickens.com/web/viewblog.php?id=1642-VENTILATION
Pat’s Cold Coop (winter design) page:
https://www.backyardchickens.com/web/viewblog.php?id=1642-winter-coop-temperatures
Pat’s Big Ol' Mud Page (fixing muddy runs):
https://www.backyardchickens.com/web/viewblog.php?id=1642-fix-a-muddy-run
2) Is there any information available to find out how much "yard" will support a given number of hens? How many sq.ft. per bird, etc...?
Another example of no magic numbers for chickens. Do you live on a mountain top in the Rockies, in the swamps of Louisiana, in the Mojave Desert, maybe in New England? You may be able to find something for your specific area but there is no magic number that covers all of us. There are too many differences in climate, soil type, rainfall, and type of vegetation for one number to cover us all.
Quality of forage is a big part of this. My parents raised chickens in the hills of East Tennessee. They never fed them during most months, just a little corn in the winter and not enough corn for them to live on. Even in winter with a light snow on the ground they could forage for a lot of their food. But they were not foraging in a manicured back yard with the grass neatly trimmed and weeds immediately destroyed. They had the run of the place. They had no fences except one to keep them out of the garden. They had pastureland, an apple orchard, and wooded areas to forage in. They got grass and weeds, grass and weed seeds, leaf mold, and all kinds of hopping, crawling, wriggling, and flying creepy crawlies. There were cows and horses so they could scratch to their hearts content in nutrient rich manure. They could go to a hay barn and eat hay if they wished, though a surprisingly few number actually did that.
Those chickens may not have laid a double extra huge egg every day of the season but the cost of food was basically zero for most of the year. The corn they got in winter as a supplement we raised ourselves. To me that is pretty efficient.
If they have good quality of forage you can cut your feed costs, but most of us do need to supplement their food.
3) Do I need to provide some type of bedding/litter for nest boxes, or will the chickens gather material on their own (assuming they are free-ranging most of the day)?
You need to provide some type of bedding for the nest boxes. They will not gather any themselves. I personally like to use straw or hay but that is just personal preference. It’s what I grew up using. You’ll find that people on this forum use about anything from wood shavings, shredded newspaper, rags, carpet, even Spanish moss. I also suggest you put a fake egg in the nest to show them where to lay. I’m convinced it helps. Golf balls work well for me.
We each have our own unique circumstances and conditions and we manage them differently. Hopefully you can get something out of this that helps.
Good luck and welcome to the adventure.
