Summer Ventilation: Ratio of low windows to high?

[whitenack]

Hey all, currently in the later stages of designing/building a new coop and trying to figure out where my windows/ventilation is going to be. I live in Central KY, so I can get cold in the winters and really hot at humid in the summers. I have my winter ventilation figured out (I will have wall/roof gaps all around the top) and I know I need more than that for summer. The question is where to put them.

From a "hot air rises" standpoint, I assume it is best to put summer ventilation lower to the ground, which would allow the hot air at the top to leave and pull in the cooler air from the bottom? If I just have windows higher up on the walls, there is no air stirring in at the bottom. I will have the pop door for lower ventilation, but that will be closed at night.

Does anyone know of a ratio of low ventilation to high?

 

[Quarterhorses1]

Hey all, currently in the later stages of designing/building a new coop and trying to figure out where my windows/ventilation is going to be. I live in Central KY, so I can get cold in the winters and really hot at humid in the summers. I have my winter ventilation figured out (I will have wall/roof gaps all around the top) and I know I need more than that for summer. The question is where to put them.

From a "hot air rises" standpoint, I assume it is best to put summer ventilation lower to the ground, which would allow the hot air at the top to leave and pull in the cooler air from the bottom? If I just have windows higher up on the walls, there is no air stirring in at the bottom. I will have the pop door for lower ventilation, but that will be closed at night.

Does anyone know of a ratio of low ventilation to high?

I would put them at the bottom, with a few small cracks at the top. I’m not completely sure though, because my entire coop is ventilated

 

[DobieLover]

Roost height windows all the way around that can be opened to allow cross breezes directly on the birds.

 

[Ridgerunner]

I don't have any hard and fast ratios, I generally don't worry about general ratios anyway. There are so many differences in what our coops look like that it would be hard to come up with something that would cover most of us. An important factor in this is the differences in temperature of the cool air coming in and of the hot air going out. To me that is more important than the size of the openings. Your extreme condition will be the calm days where there is no wind, you are solely relying on warm air rising to remove hot air.

Your pop door is probably pretty low down and open during the hottest part of the day. I don't know how cool the air is at your pop door compared to inside the coop. The coolest air should be in your north or east side unless you get some advantages of shade from trees or other buildings and probably at ground level. If that pop door is on the south or west side that air could be pretty hot if the sun can hit it.

I'd look for the coolest spot outside your coop close to ground level. Cut a hole there and cover it with hardware cloth. What you have up high should be enough for the air to leave. Have the bottom of that opening high enough so the bedding inside the coop will not block it. My chickens scratch the bedding into piles along the inside of the walls so leave a gap. That fixes the location which to me is more important than size.

Now your question, size of the opening. I don't know how tall your coop is, the size of the floor plan, if it is on the ground or is elevated, or how it is framed. I envision a decent walk-in size on the ground but that's a guess. The way I did mine, an 8' x 12' footprint and 8' to 12' coop height, stud spacing 16", was to take out a strip of the wooden wall across three studs which means 32" wide and maybe 12" high and covered that with hardware cloth. Going from stud to stud let me really anchor the ends. Like you I had openings on all four walls up high.

 

[whitenack]

Yes, you envision correctly. It is an 8x8 coop, walk-in, ground level (on concrete blocks). I went with studs 24" oc. My pop door is on the northeast side of the coop, so that should have the coolest air. I can throw in some more openings around wherever I can put them, especially on the northeast and southeast walls. I can always keep them closed if I have too many (probably no such thing).