About all we do to winterize, other than cleaning pens out and adding fresh layers of bedding, is to use heated dog dishes for water and to put up visqueen (semi-clear plastic) against prevailing winds and rain. We usually use it only on one side. The first year, I wrapped the whole complex with visqueen, but that was definitely overkill. Our pens have wire sides, but each smaller pen has a pretty snug coop. The coops are 3/4 wood sided, with wire fronts and vents for air movement. Some of our silkies choose to sleep outside their coops, and I've gone out several times to find some of them partially covered with snow--with no problems. Their "fluffy, furry" feather structure probably insulates them a bit better than some varieties.
I've coated the combs of cochins and OEGBs with Vaseline to prevent freezing. Bag balm also works.
Same here. Clean out the pens, treat for lice/mites as needed, cover the ventilated sides of coops (leaving top air gaps for ventilation), and some pens get heated water bowls. The rest have black rubber tubs that can be turned and the ice block knocked out then refilled. I also have lighting set up to give them longer daylight hours (just 23 watt CFL's on a Christmas timer). I am going to wrap plastic around the base of my raised wire brooder so I can continue to brood in the winter. If the coops have good ventilation and no drafts around the base you won't have any problems with frostbite.