Solar panels on rooftops are no longer just for those who have the money and want to be ahead of the curve. Home builders will soon have to comply with a zero Home Energy Rating System (HERS) on all homes built within the US. The short-term cost of these net zero homes will be more than a regular home, but with Government tax breaks and the low cost of maintenance on an energy efficient home, the long-term effect is easy on the wallet.
An employee of Garbett Homes predicts “within the next 40 to 50 years homes will be required by law to have a zero HERS rating.” As of now Garbett homes is the only Production Home builder in Utah to offer solar panels as a standard feature on their homes.
According to website resnet.us, today the standard HERS rating for most new homes being built is about 100 points. Each one-point decrease in the HERS Index corresponds to a one-percent reduction in energy consumption compared to the HERS Reference Home. Thus a home with a HERS Index of 85 is 15 percent more energy efficient than the HERS Reference Home, and a home with a HERS Index of 80 is 20 percent more energy efficient.
A home energy rating involves an analysis of a home’s construction plans and onsite inspections. Based on the home’s plans, the Home Energy Rater uses an energy efficiency software package to perform an energy analysis of the home’s design. This analysis yields a projected, pre-construction HERS Index.
Upon completion of the plan review, the rater will work with the builder to identify the energy efficiency improvements needed to ensure that the house will meet ENERGY STAR performance guidelines. The rater then conducts onsite inspections, typically including a blower door test, which tests the leakiness of the house, and a duct test, to test the leakiness of the ducts. Results of these tests, along with inputs derived from the plan review, are used to generate the HERS Index for the home.
Unlike a Building Performance Audit or a weatherization assessment, a home energy rating is a recognized tool in the mortgage industry. Home energy ratings can be used in a variety of ways in the housing industry. Since a rating quantifies the energy performance of a home, the HERS Index provides an easily understandable means to compare the relative energy efficiency of different homes.
For homes to be able to go completely to net zero, two or more renewable resources would have to be utilized. This could include solar, geothermal and wind energy.