Not sure which energy code requirements apply to your project? Find out!
The HERS Index

HERS Ratings

With the Massachusetts energy codes getting stricter, it is becoming harder to achieve the code mandated HERS score. Our team of RESNET Certified HERS Raters has 30+ years of experience in the industry and with over 11,000 HERS Ratings under our belt, we know what it takes to help you get the best HERS score possible for your project. We work with you to identify any weak links early on during the design stage and provide support throughout the entire construction process.



HERS stands for Home Energy Rating System, a HERS rating is the industry standard for measuring the energy efficiency of a home.  It is a holistic view of the energy usage of the home; incorporating performance testing, building materials, HVAC equipment, appliances, and lighting.  A HERS rating is the most common method to show compliance with local energy codes, and in Stretch Code communities, a HERS rating is mandatory (must get a score of 55 or less). A smooth path to energy code compliance starts with a HERS rating and a great HERS Rater.

HERS ratings can also qualify a home for other things such as utility incentive programs, $2000 45L tax credits, and certifications like Passive House, ENERGY STAR, and LEED.



We perform a suite of tests on the systems in your home to measure their efficiency.  These tests include a blower door test, a duct test (if ductwork is present), and a ventilation test.  All of these tests are non-invasive and will not disrupt or impair the home.  These test results are input in to a HERS rating software to help calculate the HERS score of the home.

To learn more, check out our article – “Performance Testing”.



A HERS rating looks at an array of building materials used in the home and calculates the impact each component will have on the HERS score.  Insulation types, depth, and quality of installation are all documented to calculate the R-Value of the walls, floors, and ceilings of the home.  Windows have performance ratings to show the insulation factor, U-Value, and how much solar energy radiates through the glass, solar heat gain coefficient (SHGC).  Additional factors including the framing factor of walls, or radiant barriers on roofs are also documented and entered into the HERS rating software.



What utilities are available on your site?  This questions drives the type of heating and cooling system that you select for your project. We will document the type, size, fuel, and efficiency of your heating and cooling system.  Domestic hot water (DHW) systems are also recorded to determine the efficiency, fuel, and type of those systems.  Distribution systems for the DHW are also examined for features including pipe insulation and total system length.  Ventilation systems are inspected to ensure compliance with applicable building codes.



The type and efficiency of your appliance package can affect your HERS score.  There are certain appliances which are known as minimum rated features, items that we will have to put into the HERS rating.  These items are the refrigerator, dishwasher, range, washer, and dryer. You don’t have to have all of these items, a default setting can be used but most appliances sold today are more efficient than the default.  We will also look whether your lighting is high efficiency LED lighting, compact fluorescent, or incandescent.




1. Plans Review + Energy Modeling

Once we receive your plans, we will use software to create an energy model of your project to show how it will perform energy-wise. We will then produce a preliminary HERS certificate which is needed by most cities and towns in order to obtain your building permit.

Depending on your budget and performance goals, we can also:
– Look at cost-effective strategies to meet code compliance
– Perform a “what if” analysis (value engineering) of different scenarios to help you get the best return on your investments
– Look at Net Zero energy options

2. Energy Consulting + Midpoint Inspection

We work with you to identify any weak links early on during the design stage and provide support throughout the entire construction process. Once the insulation work is complete, we will complete an on-site visit to locate any issues and make recommendations to ensure the project meets local energy code requirements.

3. Final Inspection

As your project nears completion, we will conduct our final inspection and perform a series of tests (blower door test, duct leakage test, and ventilation test). We will then provide you with a final HERS certificate to document compliance. This certificate is needed to obtain your Certificate of Occupancy.

If your project qualifies, we will also enroll it into the applicable Mass Save incentive program and take care of all the paperwork for you. We work with you and make recommendations to ensure you get the maximum incentives available for your project. Many of our clients who follow through with our recommendations find that the incentives help offset the cost of our services.




If your project needs a HERS Rating, please call the office at 508-833-3100 or contact us online. We service Boston, Plymouth, Cape Cod and the surrounding areas in Massachusetts.