A collage of us doing energy audits on the left with an arrow pointing to a heat pump on the right

This question comes up a lot for our Denver Metro customers and homeowners throughout the area. Heat pumps are a big expense, and you may find yourself even feverishly trying to research all the rebates, whether an energy audit makes sense, what an energy audit even is, and otherwise just how to spend your hard-earned money wisely when looking into heat pumps.

In this article, I hope to provide some clarity around what energy audits are, why they’re critically important to do before a heat pump installation, rebate information for the Denver Metro, and much more.

This perspective comes to you from myself both as a BPI Certified Energy Auditor in Denver, a heat pump installer, and with us as a company approved across the rebate programs in town.

There’s a lot to consider, but let’s dive in!

What is an Energy Audit?

You’ll probably find a few definitions and descriptions of energy audits online, but I’d like to frame it as it exists in Colorado and mostly its format for Xcel Energy rebates available, because we follow their specific procedures on this.

An energy audit for existing home is rooted in the BPI Certified Energy Auditor procedure, in which we take a “house as a system” holistic approach to a full home inspection with energy consumption, energy efficiency, and safety in mind.

We usually spend about 1.5 to 2 hours at your home inspecting everything from your attic space to your basement and crawl space, mechanical rooms, utility closets, windows, hot and cold spots, and any other specific areas of concern that you might have, in addition to much more.

It takes many hours to complete the 30-40 page energy audit report after the home visit. And after that, you will have a really great plan to tackle any low hanging fruit in terms of energy consumption and upgrades for your home.

Erin Shine with the energy audit manager for Xcel Energy doing a blower door test on a home during an energy audit
Setting up the blower door for an energy audit along with Chris Carvalho from Xcel Energy’s audit team for a homeowner in Denver.

You can check out more on our energy auditing service here as well.

Why Does This Matter For Heat Pumps?

Heat pump design is a lot trickier than just replacing a furnace and A/C combo, or just trying to replace a system with a one-for-one sizing match up. It’s a different technology (vs. a furnace or heating with gas) and performs differently too.

To properly size a heat pump system, a lot of testing should occur. I say should because oftentimes it doesn’t happen. It’s too easy for companies to do a quick home visit and just guess, knowing that sometimes it may be correct. There’s also a myth out there that because heat pumps modulate (instead of turning 100% on or off), it can make up for a lot of undersizing or oversizing issues. This is somewhat the case, but we argue it’s truly not the right way to do it.

To correctly size a heat pump, a Manual J should be done for correctly sizing the new system. A Manual J is basically an energy modeling of the whole home or space that the heat pump will be heating and cooling. It can be pretty involved, and it’s only as good as the accuracy of inputs you enter into the model. This is where the energy audit comes in.

When sizing a heat pump there are some major components and attributes of any home that can swing the heat pump sizing up or down, and oftentimes we just honestly don’t know until we enter in all the data from the energy audit. Here are just a few :

  • Insulation Levels – Attic, floor, and wall insulation levels throughout the house
  • Windows – Age, quality, glass pane count, air barrier or any e-coating for windows. Are they original single pane or upgraded dual panel, for instance?
  • Home Air Leakage Level – This is a very big one that can only be truly accurately measured by doing the blower door test (standard with any energy audit).
  • Home Attributes – Orientation to the sun, shading from trees, overhangs, location (within the Denver Metro area), wind speeds, and much more.

All of the above can heavily swing the heat pump sizing calculations drastically. And without testing or an inspection (such as with an energy audit), you/we are just guessing.

Lidar-based home scanning to determine heating and cooling needs with a floorplan scan. Every door, windows, floor, wall, ceiling, and surface input should be accurate in order to calculate actual heating and cooling loads with the engineering.

What Does an Energy Audit Include?

Xcel Energy (for rebates) follows the BPI standard pretty closely during an audit for existing homes. During our home visit, we perform a lot of tests, but here are some highlights:

  • Whole house holistic energy inspection – Inspection of all rooms and areas for anything we can spot energy and safety-related. We start with a quick chat to see if there are any areas you want us to focus on or ones that you see as a potential problem.
  • Insulation level check – attic, crawlspace, walls, floors, and more
  • Blower door test – this tells us very accurately how leaky or tight your home is as a whole.
  • Infrared Scan – while the blower door test is running, we do another sweep through your home to catch any areas that could not be seen while the blower door was not running before. The blower door allows us to catch air leaks and problem areas much better in tandem with this IR Camera.
  • Combustion Zone Appliance Testing (CAZ Test) – If you have gas-burning appliances in the home with open venting to the inside conditioned space, it’s possible that the gases may sometimes be backdrafting back into your home if there is an imbalance of pressure or airflow.
    • We perform this test on all applicable appliances to ensure they are both 1) burning and operating correctly and 2) not backdrafting or “spilling” back into your home. We want you to be breathing healthy air!
  • Bonus: Solar Potential – We like to take a look at your roof, orientation, aerial maps and more in order to offer just a quick assessment of whether solar energy would be fit well for your home. Sometimes there are trees, power lines, other houses, non-ideal roof pitches and more than might mean that solar isn’t a great fit, and perhaps a look into Colorado’s Community Solar program might be better.
    • This isn’t required but we like to include it since we have people on the team who come from the solar industry and who can design it accurately.
    • You also get an assessment without a sales person trying to sell you solar or pressuring you at all.
  • Much More

It then takes awhile to put together your full 30-40 page energy audit, but from then on you have a pretty good gameplan on what to do next! We of course help talk through next steps, whether it be heat pumps or other projects beforehand that will help a heat pump run much more efficiently.

And this is where we get into rebates, and bonus rebates from Xcel Energy as well.

Four pictures of infrared cameras and blower door test equipment used during our energy audits and includes the building performance institute energy auditor logo

What Rebates Are Available For Energy Audits?

The main rebate available is the $200 rebate from Xcel Energy if you do the full comprehensive energy audit with the items mentioned above, along with the rest of the required items we must include in the audit report.

We as a company take this on and receive it weeks later so that you don’t have to wait or deal with it. There are a couple forms for you to sign as the homeowner, but beyond that we take care of the rest. The $200 is also an up front discount so we can lower the initial cost of the audit for you.

Feel free to contact us here if you have questions on the energy audits, pricing, or if it makes sense for your home as you venture into these projects.

Xcel Whole Home Efficiency Program 25% Heat Pump Bonus

Perhaps one of the most important reasons to get an energy audit done first is Xcel Energy’s Whole Home Efficiency bonus rebate program. The short version is:

If you do three qualifying energy efficient upgrade projects within a two year timeframe as of the date of your official energy audit, you qualify for bonus rebates, including 25% bonus rebates on heat pumps.

Xcel requires that you get their official energy audit done before you can sign up for their WHE program.

If you time things correctly, and do projects in the right order, this can add potentially another thousand dollars or more to your rebates. If you’re doing multiple qualified efficiency upgrades a once anyway, it’s a really nice bonus. For instance –

  • Xcel just released a bonus of $600 if you do air sealing and insulation work before installing a heat pump or heat pump water heater. A better building envelope and lower air leakage rates only help a correctly sized heat pump to run more smoothly and efficiently, so this is a win-win.
  • You get a 25% bonus on heat pump HVAC and heat pump water heater installations on top of the regular Xcel energy rebates if you qualify for the WHE program.
  • There are additional air sealing and insulation rebates in addition to their regular ones, and we often find homeowners can drastically benefit from these improvements alongside their heat pump and electrification upgrades.

Be sure to check out our comprehensive guide on Xcel’s Whole Home Efficiency program here as well.

Wrapping It Up

I hope this was helpful, at least for a start. As someone who has been in sustainability for 20+ years, I can tell you that the energy audit is the most critical and best bang-for-the-buck first project that you can do for your home before you embark on theses (often expensive) projects with goals of energy efficiency and electrification.

Not just for the rebates, but to have an X-Ray and a data-based gameplan to help you move forward with any project or contractor you work with.

And please reach out to us to see if either the energy audit or the WHE program makes sense for you. There are pros and cons to the many paths available depending on your personal goals. And we love chatting through these with you!

Until next time, and thank you for your time.

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