When your home heats rapidly in the summertime or cools rapidly in the wintertime, it’s a sign you may need new insulation or more insulation. Finding exactly where your insulation is failing can be tricky; the heat-transfer culprit may also be your windows or doors or air leaks. You can get an energy audit, or, if you are on a tight budget, you can do one yourself. Professional audits are usually quite affordable and may be subsidized by your local utility. A good audit can help you find weak points in the building envelope you may not have found yourself. Expect to more than make up for the amount you spend on an audit with the energy-bill savings you will achieve.