Energy Rating Index Quality Management Organization

What is an Energy Rating Index?

An Energy Rating Index (ERI) is a number based on a comparison between the normalized, modified end-use loads of a computer-generated reference home and the rated home.

What the hell does that mean?

That’s a great question, and one too many people don’t ask. Partly because most people don’t know what it means (yet feel compelled to give their opinion of what it means and with absolute confidence their opinion is fact), partly because it is really complicated.

It’s our job to bring clarity out of complicatedness, and as the great physicist Richard Feynman put it: if you can’t explain something so a 6 year old can understand it, you don’t know it well enough.

I should know this well enough…I chaired the ANSI Standards Development Committee for RESNET® that developed the dang thing. For eight years…and two publication cycles.

Let’s start with the end-use loads bit.

Energy loads are the things that cause energy to be used, but do not themselves use energy. 

The end-use loads considered in the calculation of the ERI are the energy loads that cause energy to be used for heating, cooling, and hot water in a home.

In addition to those end-use loads, the ERI also deals with modified energy loads for lighting and appliances.

And the modified bit?

These loads are modified by a lot of assumptions to standardize the energy use across homes and apartments…because not everyone lives in their homes the same way…and the ERI is about the house, not the occupants.

What makes this normalized?

Oddly enough, the normalized refers to the making adjustments for the differences in relative energy efficiency between gas and electric appliances. The gas appliances got “dumbed down” to match the efficiency of electric appliances, which “normalizes” things.

What about that reference home?

The reference home for the ERI is taken from the 2006 International Energy Conservation Code (IECC).

That’s right…the 2006 version of the code.

The reference home has the same surface areas as the rated home (mostly), but doesn’t have the same mechanical equipment and the doors and windows don’t have the same orientation. There are a lot of assumptions that are standardized (like ventilation) on both the reference home and the rated home.

This means the Index number has absolutely no correlation to actual energy consumption.

The proprietary RESNET® HERS™ Index is the most used derivative of the standard ANSI/RESNET/ICC 301 ERI…for now.

How is the ERI used?

The ERI is used in the 2015 IECC and later editions as a method for demonstrating energy code compliance. The code compliance pathway of the ERI requires the rated home to meet mandatory requirements of the modern building codes. This requirement applies whether the ERI is based on Standard 301 or is the proprietary HERS™ Index.

The 2015 IECC ERI should be based on ANSI/RESNET/ICC 301-2014 since that was the ANSI standard for calculating the Energy Rating Index at the time of code publication…although that standard is not specifically referenced in the 2015 IECC.

The 2018 IECC ERI should be based on ANSI/RESNET/ICC 301-2014 as re-published in 2016, along with Addendum A & B, since that is the referenced ANSI standard in that code publication (according to RESNET®).

The 2021 IECC ERI should be based on ANSI/RESNET/ICC 301-2019, since that is the referenced ANSI standard in the 2021 code publications.

In Texas, there is a provision in state law that allows the ANSI Standard 301-2019 ERI to be used as a code compliant path, as long as the dwelling unit meets or exceeds the 2018 IECC efficiency and SHGC requirements found in Tables 402.1.2 or 402.1.4 AND meets the mandatory requirements in Table 406.2 of the 2018 IECC.

Which the HERS™ Index doesn’t do. That ERI variant has been modified through various addenda so it no longer conforms with ANSI/RESNET/ICC 301-2019, the version that existed on January 2021 as called out in Texas House Bill 3215…which expires in 2031.

Texas also recognizes that dwelling units that are certified as ENERGY STAR® are automatically deemed to be energy code compliant.

The ENERGY STAR New Homes program also uses the ERI…or the HERS™ Index, depending on which Home Certification Organization certifies the dwelling unit as ENERGY STAR.

What is a Quality Management Organization?

A Quality Management Organization (QMO) is an organization tasked with providing quality management oversight for the companies and individuals who perform the energy ratings that produce the Energy Rating Index or HERS™ Index.

The Building Science Institute is a QMO, one distinctly different from our competitor. Our Quality Management System of policies, processes, and procedures emerges from what we stand for, what we believe, and who we are.

We use software (HouseRater) that has the National Renewable Energy Laboratory-produced EnergyPlus calculation engine at its core. This provides greater consistency in software outputs while leveraging the latest research from the DOE Building America program.

We aren’t separated from our clients by a layer of middlemen. We know that consistent quality management requires a single source…and, as members of the American Society for Quality (ASQ), we are committed to act with integrity, honesty, responsibility, respect, fairness, to protect confidential information, and to avoid conflicts of interest.

We take that a step further with our corporate code of ethics…maybe more than one step. We also require that we take due professional care, maintain independence of the activity we verify or perform quality management on, and take an evidence-based approach to our work…and our clients agree to do the same.

That’s why we eliminate the concept of Rating Providers and Training Providers. This streamlined approach delivers greater consistency across the board, creating a level playing field in all that we do.

Our Quality Assessors go through at least 120 hours of training and have to demonstrate competence through actual quality management work. Much of that training is specific to quality management work and is delivered through the American Society for Quality.

We train and credential Verifiers, Software Analysts, and Quality Assessors through our brand Building Science Education to ensure that everyone operates from the same playbook.

Why?

To ensure the consistency of the work of our clients.

You see, HouseRater has a number of features built in that are designed to help our credentialed Software Analysts and Verifiers do their work correctly the first time. The best way to improve the system is to prevent mistakes, not try to catch them after they’ve been made.

These features provide us with real-time insights into our client’s work so we can help them get better…

Because our single priority is to help our clients, the verification organizations, build better businesses. 

We work with our clients throughout the year to help them improve the quality of business. Our clients hire us to help them maintain their integrity, and they help client builders maintain theirs. 

Who Authorizes a Quality Management Organization?

According to the American Society for Quality, the American National Standard Institute partner for national Quality Standards, external authorities for a quality management audit are contracts, standards (which are voluntary unless imposed by contract or regulation), or regulatory bodies which are governmental agencies authorized by law to enforce regulations.

Industry standards are NOT regulatory documents unless included in a regulation from a governmental authority having jurisdiction.

We derive our authority through proper contracts with our clients.

ANSI/RESNET/ICC Standard 301, the American National Standard for Energy Rating Index calculations, requires that a Quality Management Organization (“Approved Provider” in the standard’s language) is involved in the process.

For the first time in decades, there is a clear choice in the energy rating industry.

The Building Science Institute, Ltd. Co. is the professional Quality Management Organization for the energy rating industry.