Propane offers construction professionals design flexibility to meet code and above-code recognition programs. For example, a builder who includes a propane tankless water heater and high-efficiency furnace can scale back on window efficiency or avoid costly design changes to add thicker insulation. Because of its efficiency levels, propane-powered appliances can also be integrated into Zero Net Energy projects to further lower a home’s annual energy consumption, as measured by the Home Energy Rating System (HERS) Index.