Straight Talk Articles
Why You Oughtta Get an Audit
Dear Pat and Brad: I need to reduce my energy costs and don’t know where to start. You often recommend a home energy audit. What will an audit tell me? – Jacob
Dear Jacob: You’ve nailed it! A home energy audit is exactly the place to start if you want to cut your energy bill or make your home more comfortable. It can also help you decide whether to invest in a new energy source like a solar array or a new heating and cooling system like a heat pump, or whether it’s time to upgrade your current system.
Here’s a little checklist we’ve put together to help make sure you cover your bases.
It’s possible to do your own energy audit, using an online home audit tool(1). Your electric cooperative might even have something like this on their website. Online audit apps are a good way to learn about your energy use and possible energy efficiency opportunities. But a comprehensive energy audit provides much more.
Professional auditors conduct two levels of home audit. The least expensive, which is sometimes offered for free by an electric cooperative, is a home energy survey, sometimes referred to as a ‘walk-through’ audit that is just a visual inspection. If you have modest goals about what you want to learn from an audit, and if you are fortunate enough to find a very experienced and knowledgeable auditor, this type of audit might be all you need.
The more comprehensive level of energy audit takes more time and utilizes diagnostic tools(2). The average cost for this type of audit is $400(3). Sometimes electric co-ops will offer discounts or rebates.
The comprehensive audit will look at four main areas. The first is the envelope of your home, which includes all the places where the exterior and interior meet – roof, walls, doors, windows and foundation(4). A critical tool for testing the envelope is a blower door, which has a powerful fan that is mounted in an exterior door frame and used to de-pressurize the house. The auditor can then quantify how leaky your home is and locate the leaks. Some auditors will work with you to seal up leaks and continue to take blower door readings as the home is tightened up. One advantage of this approach is avoiding excessive air sealing. It’s possible, in some homes, to tighten the home too much, so the energy auditor can determine when to stop sealing leaks so that a healthy supply of air infiltration is maintained.
Another tool auditors use to look at your building envelope is a thermal imaging camera, which shows hot and cold spots that pinpoint exactly where insulation is needed on walls and ceilings. The camera works best when the exterior temperature is much colder or much hotter than the interior temperature.
The second focus of the audit is your home’s HVAC (furnace/AC unit) system and water heater to see how energy efficient they are and whether they should be replaced. If your home has ducts, the auditor can conduct a duct blaster test to see if your ducts are leaking and where they are leaking. Ducts located in unheated areas are often a major source of energy loss.
The third area the auditor will look at includes every other energy end use, such as lighting and plug in devices. The auditor may also suggest steps like efficient lighting or a smart thermostat.
The fourth area included in a comprehensive energy audit is health and safety. Does your home have the correct number and placement of smoke and carbon monoxide detectors? Should your basement be tested for radon emissions? Make sure you get answers to these questions.
Some audits include a sophisticated energy analysis of your home using energy modeling software. These analyses can rank the different energy efficiency opportunities in your home from most to least cost-effective. This will tell you how much you can save if you invest in all the cost-effective upgrades.
After the audit is complete, the auditor should sit down with you and explain the audit findings in detail. This conversation should include a discussion of ways to operate your home to achieve more energy savings and more comfort.
A home energy audit may seem like an extra expense, but it can save you a lot of money in the long run because it helps you make sure every dollar you put into energy efficiency pays for itself.
This column was co-written by Pat Keegan and Brad Thiessen of Collaborative Efficiency. For more information on a Why you should get on audit, go to the June 2020 More Information Page.
(1) An online home energy audit tool is at https://www.energy.gov/energysaver/home-energy-audits/do-it-yourself-home-energy-audits