Personally I find catalytic propane heaters or a 'buddy' heater to work well. Generally you can't heat the whole house but it's good enough for one room and the insulation will generally keep heat indoors. In my two bedroom townhouse we almost never run the heat because it stays a near constant 60 degrees upstairs and that's with 20 degree outdoor temps.

Lots of blankets, propane heaters, backup of an alcohol heater and a wood hobo stove for me. Worst case I head to my sister's (about 30-40 miles away) as she has a wood stove.

I also recommend keeping some oil lanterns + fuel on hand (though really you can run almost anything in an oil lantern... even vegetable oil) ... lantern fuel burns best and cleanest IMO. Adds a little heat to boot.