Ideas for adding ventilation to our truck cap coop?

We live in northern Illinois and we're getting into some extremely cold weather. This is our first winter with chickens.
We were given a small store-bought coop that our chickens were in all summer while we built a coop out of an old work truck cap. We completed it and moved the girls in about a month ago and everything has been great until now. Last night, it was about -6 in the coop with 86% humidity. (We bought a wireless thermometer that also monitors humidity.) We had every ventilation option open and could not get the humidity down. Our poor girls got frostbite, even with Vaseline on their combs.
Today I moved them back into the old coop in hopes that it is better ventilated. So far, it is a little better. It currently is 6 degrees in that coop with 73% humidity. We are hoping the frostbite won't get worse.
Anyway, we are trying to figure out how best to modify the truck cap coop to improve ventilation. I'll attach pictures so you can see the setup. There is a residential roof vent up top and we were leaving the ramp open but that is not enough. Would adding more roof vents help much?
The cap has tool boxes on the sides. We turned one of those into the nesting boxes and left the other side as is to use for storage. I though maybe we could cut a big hole in the toolbox on the other side and add the wire fence stuff (like what's around the run), creating a big "window". The door to the toolbox would act as sort of an awning over that window.
Another idea was to completely modify the roof and rebuilt a roof out of wood in an A shape and add plenty of smaller vents.
Any input, criticism, ideas are appreciated. We are new at this and want to give our chickens the best, safest coop.

And just to support the above, is there a special approach to insulation that would mitigate the condensation inside?

I have read about people who retrofit vans to travel in, and the insulation is a prime concern BECAUSE of condensation...I think they glue foam sheets to the interior metal sheathing and then cover those...some very specific ways of doing it...there are some great forums and youtube advice, may want to look at that too...

(also regarding castor oil, I think it is a very healing oil but don't know that it helps after frostbite. It will help prevent more frostbite. I lathered it liberally on my birds combs, very thick and sticky...there was quite a bit of squawking involved when I had to catch them Beekissed says she does it once a winter, I think, YMMV).

mobius said:

And just to support the above, is there a special approach to insulation that would mitigate the condensation inside?

I have read about people who retrofit vans to travel in, and the insulation is a prime concern BECAUSE of condensation...I think they glue foam sheets to the interior metal sheathing and then cover those...some very specific ways of doing it...there are some great forums and youtube advice, may want to look at that too...

(also regarding castor oil, I think it is a very healing oil but don't know that it helps after frostbite. It will help prevent more frostbite. I lathered it liberally on my birds combs, very thick and sticky...there was quite a bit of squawking involved when I had to catch them

Beekissed says she does it once a winter, I think, YMMV).

Click to expand...

thank you! I forgot to add that a few weeks ago we did notice condensation drops on the roof inside the coop. My husband insulated it with foam insulation and that seemed to help. I just bought the wireless thermometer yesterday so I have no idea what the humidity levels were before/after adding the insulation. There hasn't been anymore condensation drops inside but the window was frosty on the inside this morning.

Do be sure and test that hygrometer like @aart suggests, mine was too low by 5%. Inquiring minds want to know.

Who knew chickens would be such a science project? I had a major talk this evening with my BIL (the scientist) about coop humidity. He reminded me that humidity is relative to temperature on a hygrometer...so just identifying the relative humidity percentage has to take the temp into account. Not too helpful yet. That being said, he agreed with the frost on the window consideration as indicating too high humidity...surprised me that he was in accord.

mobius said:

Do be sure and test that hygrometer like @aart suggests, mine was too low by 5%. Inquiring minds want to know.

Who knew chickens would be such a science project? I had a major talk this evening with my BIL (the scientist) about coop humidity. He reminded me that humidity is relative to temperature on a hygrometer...so just identifying the relative humidity percentage has to take the temp into account. Not too helpful yet. That being said, he agreed with the frost on the window consideration as indicating too high humidity...surprised me that he was in accord.

Click to expand...

yes, I will have to test that out.

This sure is a learning experience! To be honest, I was not in favor of getting chickens when my husband suggested it this spring. Between our 3 kids and our dog I thought we had enough on our plate. "Let's get chickens!" He said. "They're easy and low maintenance!" He said. Bahahahaha! As we were outside last night in the -10 degree weather trying to figure out how to ventilate the coop I reminded him of that conversation. I adore our chickens and hope to get more. I have enjoyed learning about them and learning how to care for them but I definitely would not describe them as "easy and low maintenance". Haha

editing to correct myself....Actually they were pretty easy and low maintenance until the bitter cold came along, which isn't their fault.

As soon as I get through the massively STEEP learning curve which involves THIS WINTER I expect it to drop off considerably into the soothing "low maintenance" valley...

Same here. Thank you for your help and tips! I see you're in Montana. How cold does it get there?

5crazies said:

We live in northern Illinois and we're getting into some extremely cold weather. This is our first winter with chickens.
We were given a small store-bought coop that our chickens were in all summer while we built a coop out of an old work truck cap. We completed it and moved the girls in about a month ago and everything has been great until now. Last night, it was about -6 in the coop with 86% humidity.

(We bought a wireless thermometer that also monitors humidity.) We had every ventilation option open and could not get the humidity down. Our poor girls got frostbite, even with Vaseline on their combs.
Today I moved them back into the old coop in hopes that it is better ventilated. So far, it is a little better. It currently is 6 degrees in that coop with 73% humidity. We are hoping the frostbite won't get worse.
Anyway, we are trying to figure out how best to modify the truck cap coop to improve ventilation. I'll attach pictures so you can see the setup. There is a residential roof vent up top and we were leaving the ramp open but that is not enough. Would adding more roof vents help much?
The cap has tool boxes on the sides. We turned one of those into the nesting boxes and left the other side as is to use for storage. I though maybe we could cut a big hole in the toolbox on the other side and add the wire fence stuff (like what's around the run), creating a big "window". The door to the toolbox would act as sort of an awning over that window.
Another idea was to completely modify the roof and rebuilt a roof out of wood in an A shape and add plenty of smaller vents.
Any input, criticism, ideas are appreciated. We are new at this and want to give our chickens the best, safest coop.

Click to expand...

Even with ventilation and insulation, this summer your birds are going to COOK in that thing! It's like a huge broiler pan for chickens. I know this all may sound a little harsh but a truck topper just isn't ideal material for making a chicken coop.....too low a roof for any ventilation to really work, condensation like crazy(even with insulation), no light, no place for good roosting, etc. Cold, dark and wet in the winter and hot, hot, hot and airless in the summer.

Short of opening up a side and then draping a windblock so they don't have wind whistling up their skirts, I don't see any real good solutions to ventilation in this sort of setup.

What you've basically got there is a hot box. I agree that your birds will cook in summer. I've known of dogs who've died in the back of capped trucks in summer.

The problems I see for winter are that there is no way to vent warm moist air from the cap without seriously opening up some holes in it. Because there isn't much head room, that will mean all airflow will be blasting in directly at bird level. It just doesn't allow for fresh air to be drawn in low and warm air to be pushed out high above the birds heads.

I think it could make an awesome roof for a full height, walk in coop though. How many birds are you currently housing in it?

If you have no options other than to use it this winter then, yes, cut into the second toolbox and open it up like you did the other. Install a hardware cloth screen to keep out predators so you can prop the lid open and get some air in. (Propped wide open might make this coop usable in summer too.) Lower the roost. Remove the the windows in the back and line the opening with hardware cloth. Rig something so you can block off the lower half of the windows but leave the top 5-6 inches open for the whole width. This will help put airflow as high up over their heads as possible. Consider cutting some holes into the top of your big access doors up near the roofline and installing some adjustable vents there too.

Oh, and install some poop trays under the roost so you can remove feces daily to help cut down on the amount of moisture and ammonia in there.