What Is a Home Energy Audit and How Do You Prepare?

Most homeowners book an energy audit because a room is cold. They keep the appointment because of what Xcel Energy does next: the audit is the gate the utility wants cleared before it pays out its biggest efficiency rebates. Skip it, and you are paying full price for work the rebate would have covered.

A home energy audit looks at how your home uses energy, finds where it’s being wasted, and tells you which fixes are worth the money. Some people call it an energy assessment or an energy study. Same thing. Either way, it is the cheapest way to find out how energy efficient your house actually is, rather than guessing from your electric bill.

Xcel Energy recognizes REenergizeCO as the top rebate-producing contractor in the Denver Metro area, which means these auditors have walked the rebate paperwork more times than almost anyone in the state. If a cold room is what sent you looking, our guide to sealing air leaks covers the fixes an audit usually turns up first. Ready to schedule now? Call (303) 227-1000.

What Is a Home Energy Audit?

A home energy audit assesses how efficiently your home uses energy, following established building science, industry standards, and local building codes rather than guesswork. The U.S. Department of Energy defines it the same way: a proper assessment tells you how much energy your house uses and points you toward the fixes worth making.

ENERGY STAR calls it an “energy assessment” or “energy study,” used to figure out where, when, why, and how a home uses energy. The key distinction is the method: inspections, diagnostics, and a written report, not a quick walkthrough.

A typical audit at REenergizeCO includes:

• A blower door test, which checks for air leaks
• A thermal imaging scan, which checks for temperature differences
• An assessment of your home’s insulation
• An inspection of combustion appliances, like your furnace and water heater
• An analysis of your utility bills from the past year

Each of those five steps maps onto the process ENERGY STAR describes for a full home performance assessment: a homeowner interview, a review of your energy bills, a visual evaluation of your home’s exterior, interior, and mechanical systems, a safety and testing check (the blower door and combustion pieces above), and a set of prioritized recommendations at the end. REenergizeCO’s audit follows that same structure; it’s just named the way Xcel names it.

Xcel Energy refunds 60% of the audit cost when you use a participating contractor, capped at $200 depending on which services are performed. For most Xcel customers, that puts the out-of-pocket cost at $135. You pay the contractor upfront and submit the rebate form afterward, a process our Xcel Energy audit guide walks through step by step.

For the full picture of getting a Colorado home ready for winter, in the right order, see REenergizeCO’s Colorado winterization guide.

Do You Really Need One?

You can upgrade your home without an audit. Plenty of homeowners add insulation or install solar panels on a hunch. The problem: you’re spending money without knowing if it’s the right fix.

A DIY walkthrough can spot obvious problems, like a drafty window, but a professional audit is different. Per the Department of Energy, it’s equipment-based and measures the rate of airflow between the inside and outside of your house. A visual check can’t give you that.

At that price, the audit costs less than a single service call on a furnace that turns out to be fine. The price varies with your home’s size and what the home energy audit covers. In exchange, you get a written report with real findings, not a vague sense that “something” should be fixed. Sometimes that means simple air sealing and attic insulation. Sometimes it means new heating and cooling equipment. Either way, you’ll know before you spend.

There’s no substitute for the guidance a professional home energy auditor gives you. An audit means you know exactly what issues your home has, instead of guessing, and you can move forward with confidence once you decide to invest in energy-efficiency improvements. Our case for an Xcel energy audit goes deeper if you’re still weighing it.

Can You Do a DIY Home Energy Audit?

Partly, and it is worth doing first. A DIY home energy audit means walking your house with a checklist: feeling around windows and doors for drafts, checking whether attic insulation sits level with the joists, and reading twelve months of electric bill statements for the months that spike. It costs nothing and tells you where to look.

A DIY pass can’t measure. It will not give you a number for how leaky your house is, it will not find the leaks buried inside wall cavities, and it will not test whether your gas appliances are venting safely. Those need instruments. A professional energy audit puts a number on your home’s energy consumption and ranks the fixes by what each one returns.

Walk the house yourself, note what bothers you, then let an energy auditor measure it. You will ask better questions on audit day.

How to Prepare

Once you’ve scheduled your audit, there isn’t much to do. It usually takes a couple of hours. You’ll need to be home, so block real time on your calendar. Don’t try to squeeze it into your lunch break.

Here’s how to get ready:

1. Gather your paperwork. Your auditor will review 12 months of energy bills. Pull them from your Xcel Energy account online, or gather printed copies. Your bills show your real usage, room by room, not just a guess.
2. Know your home. Be ready to answer a few basic questions. When was it built? How big is it? How many rooms? Any past energy upgrades? Auditors ask these same questions as part of the homeowner interview ENERGY STAR describes as standard, so having answers ready speeds things up.
3. Make a list of problems. Write down or remember any drafts, hot or cold spots, or musty smells you’ve noticed. These often point to poor insulation or leaky doors and windows. Telling your auditor up front helps them find the cause faster.
4. Clear away clutter. Your auditor needs access to spaces many homeowners don’t think about much. Make sure nothing is blocking the attic, the exterior doors and windows, the basement, the HVAC ducts, the crawl space, the exterior walls, and the walls and roof of the garage. Make sure the water heater, furnace, and other appliances are reachable too. Got a fireplace? Sweep out the ash pit so ash doesn’t blow around during testing.
5. Close and latch windows and doors. The blower door test measures how airtight your home really is. A window left cracked open will throw off the results. Make sure everything is shut tight before your auditor arrives.

What Happens During It?

The visit usually starts with the interview and bill review covered above. Then comes the diagnostic testing.

For the blower door test, your auditor mounts a powerful fan into a flexible panel and frame that fits right in your doorway. The fan pulls air out of the house, lowering indoor pressure, and that drop pulls outside air in through any gaps or unsealed spots. What a blower door test does goes deeper into the numbers it produces. The auditor uses a smoke pencil to find exactly where those leaks are.

The thermal imaging scan uses an infrared camera to spot temperature differences along your walls, roof, and around your windows and doors, per DOE. Warmer areas show up lighter. Cooler areas show up darker. Done alongside the blower door test, air leaks show up as dark streaks in the image. It’s a clear picture of exactly where your home is losing heat.

Your auditor may also check your ductwork with a duct blower, a variable-speed fan attached to your duct system with a hose, which measures how much air is leaking out of the ducts themselves. For gas appliances, a combustion safety check confirms there are no fuel leaks or carbon monoxide risks. It also checks that exhaust gases vent correctly, so nothing dangerous builds up inside your home.

Schedule Your Home Energy Assessment

A home energy audit pays for itself by preventing problems. If you want to use less energy, lower your monthly utility bills, or get a clearer picture of your options for improving efficiency, REenergizeCO can help. Your home’s energy efficiency is the foundation of everything else REenergizeCO does to help you save energy and reduce your energy costs.

REenergizeCO’s own team of BPI-certified energy auditors handles every audit and gives you a thorough analysis of your home’s performance, plus expert-level recommendations for what to upgrade next. That matches the Department of Energy: a certified assessor should be a licensed contractor with real experience installing heating and cooling systems, windows, and lighting.

Ready to find out where your home is losing energy and money? Schedule your home energy audit with REenergizeCO’s in-house team. REenergizeCO’s professional energy auditors serve homeowners throughout Denver and the Colorado Front Range.