If you live in a house with extra rooms or bathrooms that don't get used a lot, frugal living blog The Simple Dollar recommends you seal those rooms off to help conserve energy when they're not in use.
Photo by Newtown graffitti.
When you have central air conditioning or heating, the air circulates through vents in the house. If you're not using those rooms, you're essentially throwing away money. The solution is to seal off the room so the rest of your house gets proper air distribution:
Closing off a room is pretty simple. If you have forced air heating and cooling, just close the vent in that room and keep the door closed. You can also stuff a towel or something like that underneath the door to stop the air flow even more.
You can also use this idea for the parts of your house that only see a little bit of traffic. For instance, unless you spend a lot of time in the bathroom, you don't really need to have air conditioning going in there all day. It's not a new idea, but it's always a good reminder that the smaller the area, the cheaper it is to regulate the temperature. Thankfully, you can decide that for yourself.
Close Off Unused Rooms [The Simple Dollar]