Heating and cooling only those portions of your house that you use, is one way to heat and cool more efficiently. This can reduce fuel consumption, conserve energy and save you dollars while maintaining comfort. However, in using this strategy there can be potential negative side effects that must be avoided. If there are areas of your house you don't need to use often, you can close vents and air registers to them and direct the heating or cooling to the portions of the home where you spend most of your time. Homes with central heating and cooling can benefit the most from this technique.