Keeping house thaw out? My house get's soooo cold during the winter, even when we have...

My house get's soooo cold during the winter, even when we have the fry on high.. it seem like the upper air is going right through our windows..... what are some right ways to keep the cold nouns out without keeping our heat bill HIGH?
Problems near a dented boiler ?
Answers:    You really should think around winter during the summer months. Make sure your windows are hermetically sealed tight if not caulk them. Make sure your doors are weather tight, these seal can be replaced. Check to see how much insulation your house has. All these things are constants you enjoy to stay on top of. Old single pane window need to be replaced also.
How long does it filch to fix a...
put plastic on the window, i use space heaters in the room that i am contained by at the time