Hi, We built stables for our two lads a few years back although they are wooden. My grandad always swore by facing the stable doors North. As we rarely get a northern winter blast. We have a small overhang on the front. We have little wooden shutter type window to the rear of each stable ( facing south) which we can open in the summer so they can enjoy the sun if they are shut in. We have had two terrible winters now and the stables have been dry throughout.

Our Stables when first built showing small overhang. Hope this can be some help.

The windows to the rear of the stables is open no bars or plastic. Dont think I have a photo, will try find one. It's like a wooden frame with a shutter door on a hinge that I can bolt open or closed. The opening is big enough for the horses to hang their heads out in the summer. We have aluminium plate secured to the wooden frame all the way round to prevent them chewing the wood (same on the front stable doors). I've found it helps to keep the stables airy and cool even on hot days and minimises dust.