How big should the coop and run be for 6 chickens

[The Moonshiner]

I give mine the choice. My run is roofed and I tarp the windy sides to keep snow out.
We get spells that are negative 16 at night and highs in the single digits. They can go out if they choose or not if that is their choice.

A bigger than bare minimum coop helps a ton in winter as well as making it a walk in so you're not in the wet cold weather while tending them.
For 6 in your climate a 6x8 walk in coop would give both them and you adequate space in my opinion.

 

[21hens-incharge]

And a good ventilation at the highest point under the roof. And windows that close with glass in winter and hardware cloth in the summer for lots pf fresh air.

Yes to all that.

 

[K0k0shka]

I agree with what others have said - 4 sq ft inside and 10 sq ft outside per bird at a minimum, lots of year-round ventilation overhead plus extra in the summer, and if you can, roof the run and cover the sides with something transparent in the winter, as a wind/snow block. Lots of people use clear shower curtains, I use clear polycarbonate panels that I zip-tie to the run fence. The curtains are cheaper, but tear more easily and flop around in the wind; the poly panels are a bigger upfront investment, but last much longer, are easier to use, and don't make noise in the wind.

I have the same temperatures as you, and have 6 chickens as well, and my coop is 5x7 feet. I have had varying numbers of chickens in there, temporarily up to 16 when I've grown out birds for meat (and that's only in the warm months). I've found that about 6-7 is the maximum I can fit without running into problems - fighting, smell, etc. Even if "they only go in there to lay and sleep", as some like to say in defense of tiny coops, even that is enough to require more space, as laying and sleeping are important parts of the day packed with drama and the potential for conflict - who lays where, who sleeps where, etc. The more of them you pack in there, the higher the risk of drama and conflict. And also, the more you'll need to clean.

As for roofing/covering the run, it will lower the chances for conflict even more. Chickens prefer to be outside, even when it's cold - they are outdoor animals. As long as they aren't getting soaking wet, or blown directly on by strong winds, they really don't mind being outside in the winter. So a roof and wind breaks can give them better conditions outside, so they can spend the day outside and not packed inside bored and fighting.

 

[saysfaa]

So just leave them in the coop while it’s cold with the door shut?

You can do that with a low risk of problems if your coop has a minimum of about 14 square feet of floor space per bird and good ventilation. Floor space means not counting the nest boxes, feeders, waterers, dust bath tub, and such.

It also depends on their breeds and personalities.

I have 80 square feet in a shed meant to be coop and run for them. Five hens were too many. There was no overt problems but I could see the stress in subtle ways. I know constant stress like that is not good for their health and well being. I gave the hen that was least docile to my friends who have a setup much better suited to her needs.

The four remaining hens were clearly MUCH less stressed but still some stressed by crowding. A year later, I lost one hen to reproductive problems. Observing the remaining three over the past year has shown me how a flock not stressed by overcrowding acts.

In future flocks, I will not wait so long to ease crowding if there is any.

 

[Galaxy_rules]

So just leave them in the coop while it’s cold with the door shut?

You can give them a choice by leaving the door open, or you can shut the door to keep it warmer. Both are fine. Since mine usually stay inside, I put their food and water so they can still eat and drink.