from Marty in Monroe, WI:
#493
My garage is unheated but attached to the house. Would it pay to insulate?
It would provide minimal value in reducing your bill.
I am assuming you are asking if it would pay to insulate the garage, not the house. Since you are not heating the garage, the insulation would provide minimal value in reducing your heating bill. The “payback” in the tiny energy savings could stretch out to many, many years. What is important is that your house attic be completely disconnected from the garage. Ideally, your garage should have a ceiling to prevent house attic air from directly entering the garage. If your garage has no ceiling, a vertical wall should separate the house attic from the garage. This wall does not need to be insulated.
This is important because very hot house attic air will raise the garage temperature in the summer, causing the house to become warmer, thus increasing your cooling load. In the winter, the air in the house attic is very cold and falls into the garage, thus increasing the heating load and associated energy costs.
Published Thursday, October 08, 2009