cold hardy problem?

Good Morning from AK.......
I've got an Egyptian Fayoumi who does just fine up here, I only lock the coop up in winter if it's -20 and colder. I 1st got brown eggs layers from McMurray, white rocks, black sex-links were the ones with single combs, also got Brahma's, Speck Sussex, Wyandottes. I also got surprise special pullets from Ideal, Gold Campines, an Iowa Blue, Brown Leghorn xtra large comb!, just to name a few................ all are doing well, survived the winter. Yes I got a little frostbite on some combs, little black spots, but nobody's comb fell off, and I sure didn't lose any toes. I have a 100 watt halogen bulb on a timer in my coop no heater, the hens only get 8 hrs of darkness, I guess you don't have the light problem in Maine though................... but that's all I use for heat. My coop is VERY well insulated w/ r-19 insulation and visqueen. Then what I've started doing for the walls, the chickens sometimes pick at the visqueen, I have a dog team so I have alot of feed bags, the ones that are a covered cloth I save and have started stapleing to the walls in the coop, chickens cannot peck through them, and it's a colorful wallpaper. My chickens tell me what they need. OH....................... I advise against straw, it matts down and gets to be like cement, wood shavings are great, you can find info about deep litter system to keep tour coop clean and smelling good.
Hope that helps.................................nancy