I have a 1300 sq ft square box basically, two stories. It was built in 1920 and has insulation blown in around early 80"s...the white stuff that shrinks...I am burning with a jotul castine and i have a gas furnace that was converted from the original coal burner about the size a volkswagon bug. I start a fire at six in the morning with the house at 57 and the house warms up to 75 by noon and stays warm the rest of the day... i go through about a cord of wood a year..it is fairly cold up here and long winters....my question is this i can feel the cold coming through in a few places, should i stop these or let that be my "fresh air intake"? I have carbon monoxide testers but they are the a/c plug in type and i am not so trusting of them....