Winter comfort advice needed

Hi I have a question about helping my two stray/feral kitties stay comfortable this winter. I live in southern Ontario and it is getting cold here. I made winter shelters for my cats but can only get my black female kitty to sleep in them. My orange male won't go in his shelter. I have been thinking about getting outdoor heating pads for the cats and heated water bowls. Just wondering if anyone uses them and if so any advice on brands or use? Also since orange kitty won't go in his shelter do you think it would be okay to sit it out on the deck? I feed them on the deck and that is where the shelters are. Any advice would be helpful! Thanks

Aw, bless you for taking care of these guys!

I don't have much experience with ferals, but others on this site do, and I'm sure someone will be along soon to give you advice.

In the meantime, this site might interest you:

http://www.alleycat.org/WinterWeather

Thanks for the informative link some good ideas. I'llhave to start putting sugar in their water until I get the heated water dish!