How to Understand Energy Ratings for Your House

How to Understand Energy Ratings for Your House

The Home Energy Rating System (HERS) Index (or rating) provides home buyers, sellers, and builders a means to evaluate the energy efficiency of a house. It provides an easy-to-understand expectation of the home’s energy consumption and overall comfort. A low HERS score indicates an energy-efficient home. You can improve the HERS index of your home by choosing energy-efficient designs and materials, like Fox Blocks Insulated Concrete Forms (ICF), which are compliant with ENERGY STAR and EnerGuide requirements.

How to Understand Energy Ratings for Your House

What is a HERS Rating?

The Residential Energy Services Network (RESNET) established the nationally recognized HERS rating in 2006 to inspect and calculate a new or completely renovated home’s energy efficiency (compared to another house of similar shape and size.). HERS gives buyers and homeowners insight into their home’s energy rank. It can also help builders exceed current building and energy codes, building for the future.

What is a HERS Inspection?

Fire Resistant Homes with Fox Blocks

A certified RESNET rater conducts the extensive HERS inspection of the home, from top to bottom, using HERS software. An experienced HERS rater can help a homeowner or builder adjust the design of the house to reach their desired HERS score. The HERS inspection typically costs between $1,500 and $3,000. RESNET raters look at the following characteristics of the home to determine its HERS score:

  • The air leakage rate of the finished house using a blower door test. High air leakage increases the energy needed to heat or cool a home.

  • The window’s area, orientation, shading, and insulation quality

  • The performance level of the heating, cooling, and water heating equipment

  • The energy-efficiency of the lighting and standard appliances (washer, dryer, kitchen appliances)

  • Potential distribution duct leaks within the heating, ventilating, and air conditioning (HVAC)

  • HERS considers the combustion (carbon monoxide, nitrogen dioxide, and particles) risks from gas stoves, wood stoves, fireplaces, etc.

  • The insulation levels of the thermal envelope﹘the wall, floors, ceilings, foundations, and attics of the conditioned and unconditioned spaces

Understanding the HERS Rating

The RESNET rater calculates the HERS index for a new or remodeled home by running the data through specialized software that compares the house to a standard reference home (built to code and achieving a rating of 100). The software assigns a HERS score to the new or remodeled house of between 0 and 150. For instance, a HERS rating of 50 indicates the house uses 50 percent less energy than a home built to code.

Homeowners can use the HERS rating to obtain ENERGY STAR and zero energy certifications.

  • To achieve ENERGY STAR Version 3, you need a HERS Index of at least 70-80 (20 to 30 percent better than a conventional home with a HERS rating of 100). ENERGY STAR homes have 35 percent lower energy bills and contribute 35 percent fewer greenhouse gas emissions than conventionally built homes.

  • A net zero-energy home earns a HERS rating of zero, meaning the house uses no mechanical energy. A HERS rating of zero can add three to five percent more to the home’s resale value.

The Benefits of a Low HERS Rating

Winter construction

The building or buying of a home with a low HERS rating provides several significant financial and environmental benefits:

  • Can sell for 2.7 percent more than unrated homes. For example, low HERS index homes in North Carolina sold for 9.5 percent more than non-rated homes.

  • Can save up to $178 million in annual energy bills (important to know, since heating, cooling, and water heating constitutes the highest cost of homeownership, except the mortgage loan)

  • Annually reduce carbon dioxide emissions by over 449 tons

  • Require fresh air ventilation systems, ensuring a healthy and comfortable home

  • Contain improved building techniques and materials, creating a durable, long-lasting structure with low maintenance.

Optimize Your Home’s HERS Rating with Fox Blocks ICFs

Optimize Your Home’s HERS Rating with Fox Blocks ICFs

Fox Blocks insulated concrete form (ICF) wall systems will help a home achieve a HERS score well below the Energy Star and EnerGuide requirements, contributing significantly to net zero ready and net zero homes.

  • Energy-efficient Fox Blocks ICFs as mass walls, provide continuous insulation with not thermal bridging creating a tight building envelope, and minimizing, if not eliminating, air intrusion through the above-grade walls. Houses built with ICF walls usually use 32 percent less energy to cool and 44 percent less energy to warm than similar wood-framed houses.

  • ICF walls provide further savings by lessening the heating, ventilation, and cooling (HVAC) system capacity by 14 to 21 percent compared to wood-framed walls.

  • Moisture-resistant ICF wall systems prevent moisture accumulation in the wall system, stopping damaging and unhealthy mold growth.

  • Attention to details, plus the installation of high performance windows and doors, excellent roof insulation and a Fox Blocks building envelope will meet the requirements for a Net Zero Energy Ready homes with a HERS rating less than the DOE standard for NZER of mid-50s.

Fox Blocks ICFs create comfortable, durable, healthy, and affordable homes with low HERS scores. For more on understanding energy ratings for your house, contact Fox Blocks professionals today.