Conduct a home energy audit

A do-it-yourself energy audit can teach you how to be more energy efficient and make you a more-educated consumer should you decide to hire an expert.

What you’ll save on fixes

By following up on problems, you can lower energy bills by 5% to 30% annually, according to the U.S. Department of Energy’s office of Energy Efficiency and Renewable Energy. With annual energy bills averaging $2,200, according to Energy Star, investing in fixes or energy-efficient replacement products could save you up to $660 within a year.

And self-audits can cost virtually nothing if you already own a flashlight, ladder, measuring stick, candles, eye protection, work clothes, dust mask, and a screwdriver—or roughly $150 if you're starting from scratch. As for time commitment, expect to spend two to four hours to investigate home systems, refer to utility bills, and conduct research about local norms for products, such as insulation, say experts.

Types of DIY audits

Since there are a variety of ways to conduct a do-it-yourself audit, you’ll need to know your tolerance for the tasks involved.

Some require you play home inspector, climbing into attics and crawlspaces on fact-finding missions and delving into unfinished portions of your home to look at duct work. Questionnaire-based audits rely the assumption that you can answer such questions as how many gallons of water your toilet tank holds to the R-value (thickness) of insulation in your home.

If you don’t have time to familiarize yourself with your home’s systems or confidence about diagnosing problems, are disabled, are squeamish on ladders and in crawlspaces, or are already planning to invest in a major remodel, you may benefit from hiring a pro.

Even homeowners who complete a self-audit often hire a professional to double-check their diagnoses. A self-audit may reveal drafts but not their exact source, such as ducts or insulation, for instance. Because the costs to address a draft can range from minor to major, investing in a paid audit may be justifiable.

What should you check?

All the home systems and appliances that contribute to energy costs. Here’s the breakdown of a typical home's energy usage that Energy Star references:

• Heating (29%)
• Cooling (17%)
• Water heating (14%)
• Appliances (13%)
• Lighting (12%)
• Computers and electronics (4%)
• Other (11%)

Self-audits hone in on details pros may not

While the pros use special equipment to focus on hard-to-research aspects of a home’s building envelope and indoor air circulation, DIY audits can teach you—based on the questions they ask—to identify and address the numerous small ways in which your home wastes energy.

Since lighting, electronics, and appliances collectively account for nearly 30% of the average home’s energy costs, you can make an impact on your bills by replacing old appliances with energy-efficient replacements and simple fixes—plugging appliances into power strips versus wall outlets, making sure refrigerator doors are properly sealed and don’t leak air, and opting for a programmable thermostat. 

How to spot common energy leaks

1. Check your home’s exterior envelope—the windows, doors, walls, and roof exposed to outdoor air. Hold a candle or stick of incense near windows, doors, electrical outlets, range hoods, plumbing and ceiling fixtures, attic hatches, and ceiling fans in bathrooms. When smoke blows, you’ve got a draft from a source that may need caulking, sealant, weather stripping, or insulation.

2. Check insulation R-value or thickness. Where insulation is exposed (in an attic, unfinished basement, or around ducts, water heaters, and appliances), use a ruler to measure, recommends the DOE. Compare your results against those suggested for your region via an insulation calculator.

Although examining in-wall insulation is difficult, you can remove electrical outlet covers, turn off electricity, and probe inside the wall, the DOE notes in its DIY audit guide. However, only a professional’s thermographic scan can reveal if insulation coverage is consistent within a wall. Insulation can settle or may not be uniformly installed.

3. Look for stains on insulation. These often indicate air leaks from a hole behind the insulation, such as a duct hole or crack in an exterior wall.

4. Inspect exposed ducts. They may not work efficiently if they’re dirty, have small holes, or if they pass through unfinished portions of the home and aren’t insulated. Look for obvious holes and whether intersections of duct pipe are joined correctly. Since ducts are typically made out of thin metal that easily conducts heat, uninsulated or poorly insulated ducts in unconditioned spaces can lose 10% to 30% of the energy used to heat and cool your home, says DOE.

When should a professional make repairs?

The DOE recommends calling a contractor before insulating ducts in basements or crawlspaces, as doing so will make these spaces cooler and could impact other home systems, such as water pipes. Plus, these ducts might release noxious air. DOE also recommends you hire professionals to clean ducts periodically. If you’ve noticed that some rooms get disproportionately hot or cold, bring that to a pro's attention. It could be duct related.
      
In addition, some DIY audits—like the City of Seattle’s free online audit guide, suggest hiring a pro if you suspect asbestos materials have been used in insulation or around pipes, ducts, or heating equipment. Airborne or crumbling asbestos particles are a health hazard. And a pro might be the right choice when dealing with insulation around or near electrical or examining electrical systems with bare wires.
      
A self-audit, like a paid audit, serves as a jumping-off point to help you set priorities for making your home more efficient. Whether or not you choose to make repairs yourself, one thing’s for sure: You’ll come away knowing more about your home’s strengths and weaknesses than you did before.