Stop Drafts
Doors offer many gaps for cold air to blast through. If you’re looking for a temporary solution during the cold front, invest in double draft stoppers that sit beneath the bottom of your door (they fit under windows too!). They cost less than $10 each, and immediately protect heat form leaking out and cold air from seeping in. (Side note: I suspect that you can also make these at home using round foam pipe insulation, some fabric and your sewing machine, or you can make a draft dodger using fabric and kitty litter).
Seal Your Doors
Vinyl foam weatherseal does wonders to create a tighter seal around the top and sides of your exterior doors. It’s squishy with one adhesive side that makes for quick and easy installation along the door frame. When the door is pushed shut against it, it creates a tight seal and will help keep the cold out.
Check Your Outlets
Insulate Basements & Attics
Do you have a basement to consider? While it isn’t advised to insulate the ceiling between the basement and the first floor, you can help to prevent cold air from getting into the basement by filling the end joists with insulation. Use a R-19 product cut to 10″ lengths, and fit it in between each end joist loosely, so that the soft side of the insulation was lightly against the outer wall. You don’t want it compact, but allow the thickness of the insulation to protect against cold air that may be seeping inside. For attics, use R-49.