frostbite in only one coop

[Akane]

All of the roosters in the large coop have signs of frostbite again. I left the windows open this year since only 3 birds out there are bantams. The standards and guinea fowl handle even the negative temperatures fine so in an attempt to lessen humidity this year I kept it open. They still all ended up with black combs. It's an old grain bin. 170 sq ft with a top vent, all wood, and definitely no bottom drafts. It's built so well that despite nearly 50 years of use when I rinsed it out the first summer it held water for the first 10". I had to drain it back out and dry the wooden floor. I would say it's just our weather but all the bantams I moved to the new little coop are fine despite some spilled water and no windows just a top vent. Proof that coop design not weather results in frostbite. Although I don't know the exact reason the large coop gets frostbite. The small coop doesn't stay warmer unless I run a space heater and I would think the humidity would be higher with the same amount of water in a smaller space. My humidity gauge in the large coop got lost so I can't confirm that. The grain bin works great in summer and looked like a great potential coop when I set it up but for one reason or another it just doesn't work in winter. This is the 2nd year they've all gotten frostbite and the biggest rooster has a swollen toe.

 

[chookchick]

That is very interesting. Do you have any photos of the grain bin coop? It would be nice to be able to compare temps and humidity on the same day in both coops. Could it possibly be too tight?

 

[Tala]

possibly you need a vent at the bottom to help move the air on upwards and out

Something like the same way people have sofit vents at the bottom of your roof and a round-spinny vent at the tippy top.

 

[chookchick]

Yeah, I was thinking the same thing. Possibly there is not enough temperature gradient and air movement to create a "chimney" effect. You need to go all CSI on this...It would be interesting to put some kind of draft indicator (fabric strips?) near the top vents, and see what the effect of adding a bottom vent is.

 

[SteveH]

Is there a big difference in cubic feet per chicken housed in the two coops ? More important , is the roof farther from the roost in the big coop ? It just may be that the small coop's roost is in the warmer air at the upper end of it . Without a ceiling fan running in my living room there is a 10 degree difference in temp between floor air and the 8' ceiling air on cold days or nights .

 

[Akane]

My bantams when in the big coop roosted at the top of the 16' ceiling and frostbit last year. In the small coop they roost at the top of the 9' ceiling. They like to go as high as possible. The installed roost in the small coop is only 1 1/2 feet off the ground. The ones that have been roosting down low because they aren't used to a large area are in as good of shape as the ones roosting up high. The roosts in the larger coop go from 2' to 4' off the ground. The standards cram together where 2 different heights of roosts cross so all their body heat is concentrated while the bantams are scattered in individual groups they were raised in. By body mass they should be close to equivalently stocked since one is full of standards including a whole hatch of just extra roos I had earlier this year and guinea fowl while the other contains tiny seramas, a trio of japanese bantams, and 5 or 6 12 week olds. Both coops only have top vents and are sealed up lower except the grain bin has two 6' long windows near the roof opposite each other. 1 door on each coop is left open from late morning to around dark. The thermometers read the same. I just don't have a humidity reading on one coop since the 2nd thermometer with humidity gauge got knocked down and lost.

Grain bin (the trees were cleared out)

There are some patched areas near the floor but when I sprayed down the walls with the hose it held water up to that first board before it started leaking around the doors.

Roosts were installed by going across the corners starting next to the door where they usually roost the most and going to the other window. Last year I covered that window near the door with plastic and they all frostbit so that didn't help. One thing I did forget is that the grain bin has a double layered hardwood roof. An outside layer with roofing tiles over it and then an inside layer that looks to have a 6" gap from the outer layer. I keep wishing I could take that grain bin with me since it's such a sturdy useful building with some wood that would be really expensive today and then I remember they keep getting frostbit and it doesn't seem to matter what I do.

If I was staying here another year I'd try laying plywood on the inside for some insulation and cut the back door in half so I can turn part of it in to a small centered window instead of just the ones up high. I'm renting the place though and my landlord and I have reached the breaking point. She completely agrees with all my decisions but yells at me for carrying them out. Time to find a house where I can do what I want and build a proper coop for my standards.