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A common form of energy loss is through holes/cracks in your house that let cooler air out in the summer and warm air out in the winter.  Do a check of your windows and doors for cracks or holes where air can escape.  Don’t forget to check your ceiling, floor, light fixtures, plumbing fixtures, and wall outlets for holes or cracks either.  If discovered, visit a home supply store nearby and ask for help on what to do to repair them.