We just started our chicken journey so I am learning on the fly and trying my best to prepare for things in advance. We’ve built our own coop and it’s quite sturdy. Insulation under the metal roof and in the walls. It’s 8x8’ with an 8x12’ run. We have 10 one month old hens. I found out that I’m severely allergic to pine shavings to the point I almost had an asthma attack in the coop one day. We decided to switch to sand litter for my health. We live in NE Ohio where the temps can get pretty low in the winter. I’ve been reading that sand isn’t recommended in the winter because the chickens can get frostbite on their feet. I’d be grateful for feedback or suggestions. It’s built on 4X4s and we coated the floor with rubberized material. There’s about 3” of sand throughout and we can’t go any deeper than that. There are 4 single-paned windows, two on each side, west and east. I’ve read about aspen shavings but what I’ve found are maybe too fine for a coop?