I also have CH, but second the heated blanket idea. Also electric underblankets on the bed, and pure wool cardigans/hats/blankets.
I know acrylic is cheap, but it is less than 50% as effective than wool. If you want warmth rather than style, never ever buy or use acrylic, and that goes for knitting for charity, too. Giving an acrylic hat or blanket to a rough sleeper won't help much. Better than nothing, but nowhere near as good as wool for keeping warm.
Other tips in a cold house - keep your feet up. Keep your head warm. Remember that heat rises, so don't have a bathroom window open when the heating is on if you are counting the pennies. Have a bath before bed.