Ok, I have way too many chickens for the coop I have. I have put 2x4s across the beams at the roof so they can get up there and roost. I also have 4 cages of birds that I want separate from the others for breeding purposes. Now, I have 34 babies, mostly different breeds of bantams, the outside birds are like, 97% regular sized chickens, or will be when they are grown. I have 8 Silkies and Sam is the oldest at 5 months, the others are one at about 11 weeks and 6 more at about 8 weeks. I am planning on using pallets to make an addition to my coop. My coop is a shed that I bought for this purpose but I hatched too many chicks this past summer and it's not big enough. We think it's an 8x12 but one of the kids tore the paper off the door and I'm not sure, so it might be an 8x14, pretty sure it is not an 8x16. It does not have enough ventilation to keep the big door closed during the day when snow comes. I will need this building as a place to keep the little ones until they are big enough to join the adults in the addition but be warm enough that the cold won't kill them. I am planning on covering the floor with plywood but leaving the pallet walls just like the pallets are. Not making them solid. I am planning on covering them with chicken wire, 2 thicknesses of it and covering them with tarps for protection against the wind. I am planning on using plywood for the roof. This will have a LOT of ventilation, will it be too cold for my chickens for winter? Please keep in mind that this winter is supposed to be bad.