Why You Should Add a HERS Rater or Energy Advisor to Your Pre-Construction Team

The High Performance Series

As more builders and homeowners pursue high-performance homes, one truth continues to stand out: achieving exceptional energy efficiency and airtightness isn’t a fluke—it’s the result of deliberate planning, expertise, and collaboration. And that all starts before a shovel hits the ground.

In this discussion from Advancing Prefab, industry professionals explore the vital role of adding a HERS Rater (in the U.S.) or an Energy Advisor (in Canada) to your pre-construction team. Their message is clear: if you’re aiming to build smarter, cleaner, and more resilient, you need an expert focused solely on performance from day one.

What Does a HERS Rater Actually Do?

HERS stands for Home Energy Rating System. A certified HERS Rater evaluates the energy efficiency of a home through modeling, testing, and in-field inspections. Their work starts early—reviewing architectural plans and estimating the home’s performance before construction even begins.

This modeling includes heating and cooling loads, insulation values, airtightness, and the impact of different material choices. Then, throughout the build, the HERS Rater returns to the site to conduct in-process inspections—confirming that what’s on the plans is actually being built.

Why does that matter? Because nobody wants to get to the finish line and realize they missed the mark—especially when energy code compliance or certification programs like Energy Star are on the line.

Get the Advisor In Early

Both U.S. and Canadian professionals emphasized a common theme: the earlier your energy expert joins the team, the better the outcome.

Pre-construction is the moment to catch performance issues before they become expensive construction errors. You can revise drawings, reconsider insulation, or explore different window options before they’re purchased. As Shawn St-Amour put it, "It's a lot easier to change pixels and bytes than to tear out drywall or rerun HVAC ductwork."

HERS Raters and Energy Advisors have one job: to help you build a high-performance home. While the rest of the design and construction team is busy juggling dozens of tasks, the advisor keeps their eye on the overall building performance, offering essential guidance along the way.

Beyond Code: The Power of Passive House and Energy Modeling

In Canada, Energy Advisors are often also trained as Passive House consultants. That means they bring expertise in detailed energy modeling platforms like HOT2000, WUFI, or PHPP. These tools help teams evaluate the impact of material choices, insulation levels, and window types with real numbers.

For example, an energy advisor can help weigh the performance tradeoffs between two window manufacturers or calculate the return on investing in additional insulation. That kind of input isn’t just valuable—it’s strategic.

Builders can focus on managing crews and site work, while energy advisors handle the deep-dive calculations. That division of labor keeps projects on track and ensures better outcomes.

Energy Advisors Bring Broader Perspective

One of the most valuable aspects of working with an energy expert is the breadth of their experience. While most builders stick to the materials and methods they know, energy advisors are exposed to hundreds of projects, wall assemblies, air sealing details, and testing scenarios each year.

That perspective helps avoid tunnel vision. For example, a builder might think spray foam is the only way to meet code. A HERS Rater, having seen dozens of alternatives, might suggest a different wall assembly that’s both cheaper and easier to install.

These insights come from real-world experience—lessons that advisors bring directly into your project.

Don't Wait Until the Final Test

If you’re serious about airtightness, energy efficiency, and long-term durability, don’t wait for the final blower door test to discover problems. A mid-construction test, combined with regular inspections, helps the team address small issues before they become costly mistakes.

Energy experts can also identify solutions quickly. If a leak shows up, they’ve likely seen it before and can recommend a quick fix. It’s this hands-on troubleshooting that transforms a build from code-minimum to performance-optimized.

Expanding Roles: From Air Sealing to Embodied Carbon

In places like Vancouver, energy advisors are going even further. In addition to performance modeling and airtightness testing, many now provide embodied carbon analysis, helping clients understand the carbon footprint of their building materials.

This is critical in the push for sustainable construction, as upfront carbon emissions are becoming just as important as operational energy use. By factoring in both, builders can deliver homes that are both high-performing and environmentally responsible.

Where to Find a HERS Rater or Energy Advisor

For those in the U.S., the Energy Star website provides a searchable database of HERS Raters. Simply head to EnergyStar.gov and look for “Find a Rater” to connect with certified professionals in your area.

In Canada, most provinces maintain lists of licensed Energy Advisors through organizations like Natural Resources Canada. These advisors can assist with HOT2000 modeling, blower door tests, and third-party verification required for energy incentive programs and code compliance.

Many also hold additional certifications in Passive House, net-zero, or carbon accounting—making them a key part of any high-performance build team.

Final Thoughts

High-performance homes don’t happen by accident. They’re the result of clear planning, smart design, and expert collaboration.

Adding a HERS Rater or Energy Advisor to your team isn’t just smart—it’s essential if you want to meet today’s energy codes, certification targets, or sustainability goals. Their ability to analyze plans, test performance, and troubleshoot problems ensures that every home is not just built—but built right.

Whether you're working on a new build, a retrofit, or pursuing certification, make sure you have the right people at the table from the very beginning. The investment will pay off in performance, comfort, and long-term durability.