This is to the OP and others who might be reading this. What the OP is finding out the hard way is that functional chicken coops are NOT something you throw together just any old way and expect to have success. The Woods coop referenced by JackE was designed and being promoted in books well over 100 years ago. It, and others like it, were the product of years of research into what was the optimal coop to raise birds in. That during a time when flocks such as ours were present on nearly every farm and on backyard lots all over the country. Flocks that mattered. Flocks that put food on the table and money in the cookie jar. What nearly all of those books also included was a photo and reference to what the authors described as exactly what NOT to do. Dark, wet, poorly ventilated coops. Death traps.
By comparison, the coop that JackE shows was researched to the point where every aspect of that coop had been optimized for success. From the size and orientation of the wide open screened openings, window size and placement. Door placement. Orientation of roosts and nest boxes. Up to and including not only to set the coop on a dry, elevated site with openings facing south, it was openings facing a few degrees east of south to take full advantage of the winter sun.
In general.......we do none of that. We take what is proven and known to work and ignore it completely. Generally this is not done on purpose, rather out of ignorance (not stupidity). In short, we fail to do our homework. Instead, we often go to great lengths to put something together we think will work or worse, what we think is "cute", and in the process, seem determined to reinvent the wheel, which often turns out to be square when we are done with it.....then wonder why it doesn't work. BTW, this is not unique to us individuals. I know of a local place that builds and sells small farm sheds, garden sheds, etc, and they also make and sell a few chicken house designs that are truly horrible. There is an old saying......."form follows function". This is especially true of livestock buildings. Stray from what is known to work and you pay the price. Rather, the livestock pays the price. Usually, the penalty is death......and from no fault of their own.
So, to the OP..........in the photo provided, what direction is south? You should strive to have all areas of the coop that are open to face south into the winter sun. You will need roughly 1 square foot of open, natural ventilation space per bird. So 40 square feet of open ventilation that requires NO form of electric power to achieve. Goal is also to accomplish this without having any significant air movement (drafts) inside the coop.....and especially not where the birds roost. Not an easy thing to do. So for the most part, that means vents far apart from the birds on the roost. Consider using rectangle shaped gable vents of the type used in houses and garages. Replace the screens with hardware cloth so they don't clog up. In general, those shed rain and snow, yet still allow a low of air to flow through.
You are smelling ammonia now. What is also present that you are not aware of is water vapor from the birds themselves......from their breath and droppings. That is about to show up BIG TIME in the form of condensation, which will lead to frostbite on your bird's combs and wattles. Worse if that is an uninsulated metal roof above the birds. That is about to start raining down on them if it has not done so already. An abundance of natural ventilation is your best remedy for both of these.
Also consider moving towards deep litter. That will absorb both the N in the droppings, as well as the water. By deep, start with 4 to 6 inches and add more as needed. Even they, you may need to remove the stuff beneath the roosts often. 40 birds generates a lot of manure and you will need a place to go with it.
By comparison, the coop that JackE shows was researched to the point where every aspect of that coop had been optimized for success. From the size and orientation of the wide open screened openings, window size and placement. Door placement. Orientation of roosts and nest boxes. Up to and including not only to set the coop on a dry, elevated site with openings facing south, it was openings facing a few degrees east of south to take full advantage of the winter sun.
In general.......we do none of that. We take what is proven and known to work and ignore it completely. Generally this is not done on purpose, rather out of ignorance (not stupidity). In short, we fail to do our homework. Instead, we often go to great lengths to put something together we think will work or worse, what we think is "cute", and in the process, seem determined to reinvent the wheel, which often turns out to be square when we are done with it.....then wonder why it doesn't work. BTW, this is not unique to us individuals. I know of a local place that builds and sells small farm sheds, garden sheds, etc, and they also make and sell a few chicken house designs that are truly horrible. There is an old saying......."form follows function". This is especially true of livestock buildings. Stray from what is known to work and you pay the price. Rather, the livestock pays the price. Usually, the penalty is death......and from no fault of their own.
So, to the OP..........in the photo provided, what direction is south? You should strive to have all areas of the coop that are open to face south into the winter sun. You will need roughly 1 square foot of open, natural ventilation space per bird. So 40 square feet of open ventilation that requires NO form of electric power to achieve. Goal is also to accomplish this without having any significant air movement (drafts) inside the coop.....and especially not where the birds roost. Not an easy thing to do. So for the most part, that means vents far apart from the birds on the roost. Consider using rectangle shaped gable vents of the type used in houses and garages. Replace the screens with hardware cloth so they don't clog up. In general, those shed rain and snow, yet still allow a low of air to flow through.
You are smelling ammonia now. What is also present that you are not aware of is water vapor from the birds themselves......from their breath and droppings. That is about to show up BIG TIME in the form of condensation, which will lead to frostbite on your bird's combs and wattles. Worse if that is an uninsulated metal roof above the birds. That is about to start raining down on them if it has not done so already. An abundance of natural ventilation is your best remedy for both of these.
Also consider moving towards deep litter. That will absorb both the N in the droppings, as well as the water. By deep, start with 4 to 6 inches and add more as needed. Even they, you may need to remove the stuff beneath the roosts often. 40 birds generates a lot of manure and you will need a place to go with it.
