Most sheds with vents still don't provide enough ventilation to house chickens so be prepared to make significant modifications (adding soffit vents, covering all openings with hardware cloth, etc.).
Yeah I'd agree with this if you're closing all the doors and keeping them INSIDE of it all day.
We have a hygrometer inside our shed (shows temp and humidity), during the daytime, its 3-4 degrees hotter than outside and the same humidity. This is with the door completely held open, window open, vent fan going (which sucks air out from the top of the shed) and side door open.
As dusk falls, this evens out and by bedtime, it is the same ambient temp as outside. It does *not* hold heat.
Since it isn't getting insanely hot here anymore, we're not rushing to do this, but the plan is to make a 'screen door' out of one of the doors lower quarters, for more air to circulate through at night or if we need to keep them in for some odd reason in the summer. We will have a run for them to go out in by then.
The shed also creates some glorious cool shade on the lee side that stays several degrees cooler than any outside temp and when it's warm and they are dozy, they hang out around there.
Depending on what you're going to do with it, just don't keep them closed up in just the shed all day long without adding extra ventilation. The windows already installed aren't that much of an extra expense and a solar vent fan - we got a 10" one, is about 80 bucks. It only works when the sun is out, but when the sun isn't out, its not hot enough to warrant it.
As far as 'bad air' is concerned because of chicken poop build up -- I use roosting tables - my husband built them from scratch to fit the shed and the height I wanted for me to easily reach. I clean them every day and pick up what poop I can see easily on the floor -- there is barely any on the floor as they just use the shed for roosting, mainly.
Please feel free to say whatever ideas you have!
