Home energy rating

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A Home Energy Rating is a measurement of a home’s energy efficiency. Home energy ratings can be used by for both existing homes and new homes. A home energy rating of an existing home allows a homeowner to receive a report listing options for upgrading a home’s energy efficiency. The homeowners may then use the report to determine the most effective ways in which to upgrade the home’s energy efficiency. A home energy rating of a new home allows buyers to compare the energy efficiency of homes they are considering buying.

1 Usage
2 HERS Index
3 Projected and Confirmed Ratings
4 See also
5 References

[edit] Usage

The HERS Index.

A home energy rating can be used to gauge the current energy efficiency of a home or estimate the efficiency of a home that is being constructed or improved. A home energy rating of a home prior to construction or improvement is called a “projected rating.” A home energy rating that is used to determine a home’s current efficiency is referred to as a “confirmed rating.”

Energy assessments take into account different climatic conditions in different parts of the country and are benchmarked according to average household energy consumption particular to a given climatic region.

[edit] HERS Index

Ratings provides a relative energy use index called the HERS Index – a HERS Index of 100 represents the energy use of the “American Standard Building” and an Index of 0 (zero) indicates that the Proposed Building uses no net purchased energy (a Zero Energy Building).

For capitalizing a building’s energy performance in the mortgage loan, certification of “White Tags” for private financial investors, and by the federal government for verification of building energy performance for such programs as federal tax incentives, the Environmental Protection Agency’s ENERGY STAR program and the U.S. Department of Energy’s Building America Program.

[edit] Projected and Confirmed Ratings

Projected ratings give home owners and builders an estimate or what a home’s efficiency will be like after construction or improvements, so that they may determine the most cost-effective route to improve a building’s efficiency. A confirmed rating, which indicates the home’s current efficiency, requires an inspection of the home from an energy rater. The home energy rater reviews the home to identify its energy characteristics, such as insulation levels, window efficiency, wall-to-window ratios, the heating and cooling system efficiency, the solar orientation of the home, and the water heating system. Performance testing, such as a blower door test for air leakage and duct leakage, is usually part of the rating.