I've had Silkies and never had a problem with them in the cold even below temps. They just snuggle within each other and warm as they can be! Like one said, they look like a pile of dirty clothes!
ARE SILKIES WINTER HARDY? - Page 2
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The feathers on a Silkie are actual feathers, not fuzz. On a hard feathered bird, between each single hair that is attached to the shaft, there are microscopic "hooks" made of cartilage. They are called Barbicels, and act a lot like velcro holding the hairs together. Aside from a few primary flight feathers, Silkies do not have these barbicels, therefore each hair is allowed to fly free, causing the look of fur instead of feathers.
As well, Silkies are as cold hardy as any other breed. There is a common misconception that Silkies are extra insulated, making them extra cold hardy in cooler temperatures. In fact, they have no more feathers than any other breed, therefore they are not insulated any more than any other bird is. Take the same precautions you would any other bird, and put a heat lamp out for them in extremely cold temperatures for extended periods of time.
Just because they look different, they should not be treated any different than any other bird, unless your showing them of course. Otherwise, give them the same amount of heat when they are young, treat them the same as any other bird when they are adult, and they should be fine.
I use heat lamp attached to thermo cube (turns on when the temperature goes below 35F and turns off when it raises to 45F) just to make sure the water is not frozen. The chickens don't seem to get closer to the heat lamp or move far - they are as usual - so I guess they are fine with moderate cold weather. Whenever the heat lamp goes off in the middle of the night, they think its dawn and start crowing already (I have 5 silky roos and 4 hen - LOL )
We live in northern Nova Scotia, which would have colder winters than most parts of the U.S. Our silkies are at least as winter hardy as our other birds. Their coop is unheated, though not drafty. No cold-related fatalities.
Unless it is bitter cold, we open the coop door during the days, and let the birds decide if they want to go outside. On days that the other birds won't step outside, the silkies will still go out, and I see them scratching in the snow looking for food.
Their feet also are better snowshoes than the other birds.