A lot of earth-conscious homeowners have big plans: wind turbines, solar panels, geothermal wells, hybrid home appliances. It’s fine to dream big when it comes to green projects, but make sure you have the basics covered first. Adequate insulation should be at the top of your checklist. The right amount of insulation can lower your heating and cooling bills by 20 percent—not to mention, it’s easier and cheaper to install than your average wind turbine! Insulation standards have changed over time, meaning most homes don’t have nearly enough. Your attic should have between 19 and 22 inches of blown-in or batt insulation.