Safe temperature range for birds in Canadian winters

With Toronto weather swinging wildly, what temperature do you keep your bird room at? My African Grey seems uncomfortable. Also, is the dry air from forced-air heating a concern? Should I get a humidifier?

Bird Sitting Toronto has a great blog with articles on this topic actually. Worth checking out!

The Toronto Humane Society sometimes has birds available for adoption too. Worth checking if you're in the downtown area.