I would get that sand right out of your coops. That stuff is no good in cold climates at all. It provides no insulation and it does not keep dry in the wet and cold. People have made their chickens sick with respiratory issues by using sand in the winter coop. Switch to straw.
I didn't like straw at first because the strands get everywhere and it's hard to sweep up -- but in the long run I'm glad we chose it over shavings. The hens love chewing on it and throwing it over their back -- even when they come across strands of it on the ground they'll stop to nibble and throw it over themselves and walk on. However I don't find that straw stays particularly dry and we check it daily for any moisture spots from poops, rain leaks, or the rare broken egg in a box. But since I've never used anything but straw in the coop I can't compare it to other beddings -- I just like the fact that our hens seem to really like it.