How big does the sleeping coop need to be?

[J99]

I heard the run should be about 8/10 square foot per chicken , but how about the sleeping area?

 

[Folly's place]

Chickens should have at least four sq. ft. per bird, and preferably more, in a roofed weather and predator protected coop. It's not a 'sleeping area'! There will be times, during bad weather and predator visits, when the flock might be in for two or more weeks at a time. Too small, and nasty behaviors will happen. Your roofed run can be part of this area, if it's also predator proof. Otherwise, the coop needs to work for the entire flock.
Mary

 

[Folly's place]

Not bad! And Polish too!
How much ventilation and light?
Mary

 

[rosemarythyme]

can tons of perches help?

Yes and no. You want to give them around 12" of roost per bird to allow them to get up and down easily, and to jostle for favored spots, but if you just cram a bunch of roosts into a small area, you could end up with birds picking at each other due to crowding, or simply pooping on each other, depending on how it's all set up...

 

[Shadrach]

I have a multi coop system; related individuals share one coop in general. I have 4 different groups at the moment.
The coops are small and off the ground. The chickens have free choice of which coops they live in.
The most important point is the chickens here free range every day from a about an hour after sunrise to dusk every day no matter what the weather.
I've had a group of hens, 4 in this case, who shared a coop for sleeping and egg laying that gave then less than a foot of floor area each. This is what they chose.
I have another coop where the occupants have a bit more than 3 square feet per fowl (Bantams) and half of the coop doesn't get used.
So, I think that your climate, breed and keeping arrangements are more important than a square footage recommendation.
If you expect weather conditions too harsh to free range in and you have unrelated mixed breeds then 4 square feet is probably not enough space if the chickens are confined for any a number of days or weeks.

 

[J99]

Ok well I don’t have the funds to build on at this point and I’m not culling anyone so they’ll have to be tight this year. Now knowing that, can tons of perches help?

 

[BigBlueHen53]

How big is your "sleeping area," and how many birds do you have? If you add more perches, will they be pooping on each other's heads? Too many birds in too small a coop, as mentioned above, can lead to destructive behaviors. The dominant birds may prevent the subordinate ones access so some may sleep outside, subject to predators and extreme weather. They can harm each other and then you may have to isolate birds to deal with wounds. In severe cases you may even have to deal with cannibalism. There is a reason for the "four square feet a bird" recommendation. It's not just an arbitrary number, and it's not just to provide luxury accommodations. It's what the birds need.

 

[J99]

My “ sleeping area” is 112 square footage roughly 3.5 per bird

 

[J99]

Three windows but not much light at all and cracks all around and a gap at the roof and walls

 

[Lizzy733]

More is better - go for bigger than needed and you won't regret it. My run is 6mx5m - 30sqm and my coop is sized for 6 birds at 1.2mx2.4m with a little over 2m of perch space. This is currently housing 4, but we will be adding +2 pullets from our recent hatch.
Extra space will give you the flexibility to section off the run if needed for integration\separation\replanting etc... and is better for their wellbeing. They will use all the space you give them so there's no such thing as too much.