Saving energy is on our minds these days, and is one of the best reasons to choose a new home when you’re ready to move. New homes are intrinsically more energy efﬁcient than most dwellings you’ll ﬁnd on the resale market.
But there’s one more step you should take to ensure your new home will be the best it can be—independent energy testing. Using uniform testing and industry standards, certiﬁed energy raters will provide a consultation and comprehensive data about each home’s performance to the builder and their buyer. Testing will also provide a Home Energy Rating System (HERS) index number that is easy to understand and compare for those of us who aren’t building scientists.
“Independent energy testing is a win-win for everybody,” explains Ross Anderson, an energy efficiency consultant, speaker, and educator with The Energy Network Worldwide. “Especially today with builders and their trades so busy, we provide another set of eyes.”
Many builders already rely upon energy consultants to ensure their homes meet or exceed code. And local utilities help by offering rebates that offset costs. “With their mandate to reduce energy consumption, utilities actually incentivize builders to build more energy efficiency into their homes,” says Anderson.
Certiﬁed energy raters, like Anderson, work with your builder during construction to check speciﬁc energy features before they’re hidden behind the walls. “We ﬁrst do an insulation inspection prior to drywall,” notes Anderson. “The goal of this inspection is to ensure that all air sealing techniques have been done properly and to ﬁnd any issues that would reduce the home’s energy efficiency.”
The rater then returns at the end of construction to perform a ﬁnal inspection. “The goal of the ﬁnal visit is to test the integrity of the home and verify the equipment used is the best possible,” Anderson says. “We analyze the major power users, including all appliances (refrigerator, dishwasher, washer/dryer, water heater, furnace, and air conditioning) as well as the ventilation system.”
This Final Inspection Includes…
BLOWER DOOR TEST:
This test determines the exact amount of air leakage in a home. The rater depressurizes the entire house, then measures the airflow between inside and outdoors. The test results in a number called ACH (air exchanges per hour). Minnesota code requires the ACH be three or lower; a higher ACH will waste more energy. You’ll see this number listed along with the HERS on your Minnesota Green Path Home Performance Report (HPR).
Using an infra-red camera, an energy rater scans all the walls, floors, and ceilings to locate any differences in surface temperature throughout the home. Any identiﬁ ed “hot spots” indicate air leakage which can then be corrected.
Heating and cooling ductwork can be a big energy waster. This duct test is similar to the blower door and is used to detect any leakage as air flows through the ducts.
ERV/HRV (ENERGY OR HEAT RECOVERY VENTILATION SYSTEMS):
Saving energy means building air-tight homes. The ﬁnal inspection also examines these systems which are designed to provide fresh air to the interior.
HERS INDEX NUMBER:
With tests completed, the energy rater inputs the results into a standardized computer modeling program that computes the performance of a particular home against an index (a typical home of the same type/size). The resulting HERS number can be compared to the code reference home (HERS of 100), and to other tested homes. The lower the HERS, the more efficient the home. With the ﬁnal inspection complete and any discovered issues corrected, the home is ready for move-in. The owners can be assured that the home they purchased will live up to its promise to provide a comfortable, healthy, and energy-efficient residence for long into the future.
Whether your goal is to lower your energy costs, to lower your environmental impact, or just to make sure the home you buy is built to the best possible standards, having an independent energy rating is a great choice. You can start by reading more about energy efﬁciency in new homes at MNGreenPath.org. Then tell your builder you’d like your new home to include independent energy testing and a MN Green Path Home Performace Report (HPR).
Written by Wendy Danks
Wendy Danks (wendydoodles.com) has had a career-long love affair with the Parade of Homes, spending the last 20 years as its marketing and communications director. Recently retired, she now has time to spend on her other great love, writing.