Are you ready for maximum energy savings? Several programs and standards will give you a target to aim for.
If your renovation is going to be a complete gut rehab—stripping all the building envelope walls down to the studs—you can aim for certification through a new-home program like ENERGY STAR. To qualify, your home must be inspected, tested, and confirmed through energy modeling to meet rigorous criteria for reduced energy use.
Find out if there’s a green building program in your area that sets standards for home remodeling. Examples of such programs include GreenPoint Rated in California, Minnesota GreenStar, and EarthCraft House in the southeastern United States. Such program guidelines usually call for testing and inspecting the home before and after the work and documenting the improvements made. These programs can help you qualify for rebates and tax incentives that can put thousands of dollars back in your pocket.
If you want to seriously reduce your energy use, consider a deep energy retrofit, which targets reducing energy use by 50-90%. This is accomplished primarily by beefing up the building envelope: sealing air leaks, adding wall and roof insulation, and installing high-performance windows. These measures greatly reduce summer heat gain and winter heat loss, so your heating and cooling equipment needn’t work as hard to keep your house comfortable. The “1000 Home Challenge,” an initiative of Affordable Comfort, Inc. (ACI), aims to support deep energy reductions in 1,000 homes around the country; their web site provides information and support for the process.
Want to go even farther? Consider shooting for net zero energy (NZE) or zero peak levels of energy performance. A net zero home produces as much energy on-site as it uses over the course of a year. Although in theory this could be achieved by an energy hog of a home with lots of PV, it’s generally best to make the home as efficient as possible before installing PV, as previously explained. A zero peak home is designed to draw no electricity from the power grid during peak hours. This lowers the utility company’s need for expensive fuel sources and power plants to meet peak demand.
Finally, Passive House—a standard developed in Germany and now gaining popularity in the United States—emphasizes improving the building envelope more rigorously than any other standard. Many homes built or remodeled to the Passive House standard can be kept warm in winter with only a small heater; the insulation, air sealing, and ventilation are so effective that body heat and household activities (such as cooking and showering) provide most of the heat. However, this is a challenging standard to meet in new construction, and even more challenging in a remodel.