I bought some sub freezing sleeping bags too. I worry that the power will be out for an extended time, and we will have to sleep in them inside the house to keep warm. I also have a tent that will go up in the living room and we could sleep in our bags inside of it to controll heat loss and prevent drafts. I am thinking of heating a very small space like a single room with a ceramic heater. It would make sense to plan on organizing your living plan for a small space ahead of time just in case.