Ventilation on new coop

[mbodamer]

Hello,
We have tried to do my research and found the consensus seems to be 10% of floor space for ventilation. We are in the process of making a 4x8 coop and it is covered by an existing overhang from a garage/shed. The soffit of the existing building has vents and there is a ridge vent on the roof. We planned on putting plywood on the ceiling and making vents but then I thought maybe I cold put the plywood on top of the ceiling joists and then use hardware cloth in the area between the joists and we would have 8 linear feet of venting that is 4 inches tall all along two ends of the coop. Probably hard to visualize I know.

This should give me more then the 10% floor space for ventilation but I am still concerned if:
#1) is it enough
#2) i wouldnt have a way initially to open/close it (would i need to)

We are planning on installing two basement hopper style windows for light and they of course would be able to open as well.

Thoughts?

 

[mbodamer]

here is a picture of it under construction. maybe it will help to visualize. I do not have the ceiling on yet. I was thinking maybe HC the entire thing since it will just go up into attic space of the rest of the garage. is that too much ventilation? I also thought about HC the entire thing but make two wooden boards that can slide over the HC ceiling to control airflow if needed and the could be slide over the top from inside the garage. Aslo thought about putting the plywood on top of the rafters as originally stated and let the space between the rafters and the walls remain open with HC. the final option was to just plywood the entire thing and put 3 basement hopper windows in as close to the top as we can get them???

 

[lazy gardener]

IMO more is better. My 10 x 12' coop has 24 s.f. of standard ventilation: 3 windows, floor level vent, eave and soffit vents. In addition, there is an other 35 s.f. of ventilation which includes pop, clean out, people, nest box, and broody area doors. On a hot summer day, I can open it all up. In the winter, the soffit and eave vents are always open, pop door is open during the day, and window(s) are open to varying degrees. My winter temps often go down to minus 20*F. Often there may be a week or more at a time when temps don't even get up to 0*F!

IMO, 10% of floor space or 1 s.f. per bird is minimal ventilation. Choose which ever number would be larger. Also, realize that the higher your winter stocking density, the greater the likelihood of frost bite.

 

[ClockRoach]

In the summer, there's no such thing as too much ventilation. As long as a cold breeze isn't going straight up their cloacas, they'll be fine, more or less. In the winter, it depends a lot on your local temps, winds, and humidity, but in general you should worry less about keeping them warm than about protecting them from drafts and breezes.

Having the whole ceiling open with hardware cloth usually means that all the noxious fumes and some of the dust can escape without the coop being drafty. I also have some panels that I can slide over top when it gets especially cold, and that tends to work well.