EnergyWiseSM Tip: Ducts

August 13, 2021

By: Energy Efficiency Program Manager Cory Fuehrer

Pop quiz: What could be wasting up to 20% of your home’s energy use each year? Here’s a hint. It’s not your children’s video gaming systems or cell phone chargers. Rather, it’s something you rarely see and likely wouldn’t consider unless you have heating and/or cooling problems.
Give up? It’s your ductwork! About 90% of Nebraska homes have a furnace, air conditioner or heat pump connected to a centralized ductwork system. According to ENERGY STAR®, up to 30% of the heated or cooled air that moves through ducts could be lost to leaks, improperly sealed joints, or a lack of insulation. Leaks and seams are responsible for inefficient heating and cooling, but something called heat conduction also shoulders some of the blame. According to the Department of Energy, this phenomenon, in combination with air leaks and gaps, can reduce the efficiency of heating and cooling systems by as much as 40%. Since about half of the energy used in Nebraska homes is attributed to space conditioning, that equates to an overall annual energy loss of 20%!
Why? Your home's duct system is a branching network of rectangular and/or round tubes in the walls, floors and ceilings that carries heated or cooled air from the home's heat pump, furnace, or central air conditioner to each room. Duct sections are usually made of sheet metal, fiberglass or other construction materials. Duct loss occurs when conditioned air in a home escapes the duct system through holes, loose connections or improperly sealed junctions between sections. Loss also occurs as heat transfers directly through the walls of the duct itself. These losses are usually from the effects of poor duct installation, insulation and/or design practices.
How would you know if you have duct problems? Here are common symptoms:
• Rooms that are hard to heat or cool – Rooms that are not cooling or heating properly usually means that the ducts are not transporting sufficient amounts of conditioned air to and from them.
• Dust can be found on flat surfaces after running the furnace or air conditioner – Dust can be drawn into leaky air return ducts, make it passed the filter and blow the dust into conditioned rooms.
• Higher utility bills – If ducts cannot transport air properly through a home, the heating and cooling system has to run longer, which requires more energy and costs more money.
Before contacting a certified HVAC technician, there are some simple, inexpensive steps you might try to resolve duct issues:
Step 1. Turn on your furnace or air conditioning system.
Step 2. Locate air ducts (typically found under floors, in ceilings, and in attics and crawl spaces).
Step 3. Feel along the sides of ducts to spot escaping air. Leaks are found at connections to vents and registers where they meet the floor, walls and ceiling. Remember that the s-cleats (where sections of duct connect) are also notorious for leaking.
Step 4. Seal with mastic-type sealant and/or butyl, foil or other heat-approved tapes that are labeled with the Underwriters Laboratories (UL) logo. Mastic sealants are applied with a paint brush and work great for leaks less than one-quarter inch wide. Heat-approved tapes are great for wider gaps and holes in ductwork.
Step 5. If any of your ductwork runs through areas not heated or cooled, remember it requires proper insulation. When uninsulated ductwork extends through unconditioned attics, basements or crawlspaces, heat can easily transfer directly through the duct wall. Thus, cooled air will heat up during the summer and heated air will be cooled during the winter before it gets to the room being conditioned. Also, uninsulated ductwork running through warm, humid areas will cause moisture problems since humidity will condense into liquid water on the duct’s surface.
Finally, if you are unable or prefer not to resolve your system’s concerns through the steps above, it is best to contact an HVAC technician certified through an accredited organization such as the North American Technician Excellence (NATE) program. This helps provide assurance your duct problems are appropriately resolved the first time!
To identify more ways to manage your energy costs, visit with Southwest Public Power District or Nebraska Public Power District. They are committed to helping customers make the most of the energy they use, which includes keeping homes warm in the winter and cool in the summer. You may also qualify for EnergyWiseSM energy efficiency financial incentives to offset the cost of making your home more energy efficient. Contact Southwest Public Power District or visit www.nppd.com to learn details.
October 22, 2025
Looking to save energy and still stay comfortable at home this fall? A few small tech upgrades could make a big difference. · Smart plugs can help you control when appliances and lamps are on — even when you’re not home. Set schedules or turn devices off from your phone. · Smart thermostats learn your habits and adjust the temperature automatically, saving energy without sacrificing comfort. Some models also give you detailed reports on your energy use. · LED strip lights are a trendy way to light up kitchens, bathrooms and even outdoor areas. They use little electricity and last a long time. · Smart power strips stop electronics like TVs, computers and game consoles from drawing power when they’re turned off. · Motion-sensor lights work indoors and out. Try them in hallways and entryways to prevent leaving lights on by accident.  With daylight hours getting shorter and temperatures dropping, now’s a great time to explore smart tech that helps save money while keeping your home cozy.
October 16, 2025
As cold weather begins to set in, many people retreat to their garage to escape the chill. As do vehicles, so drivers hope to avoid scraping off ice and snow in the morning. If there’s any space remaining, ongoing projects are moved in with hopes of finishing them soon or carrying them over until spring. Closing up the doors and windows, many start using supplemental heat to make their garage, shop or shed even more hospitable. Propane tanks are filled. Pilot lights are ignited. Space heaters are plugged in. Then, without much thought, thermostats are turned up to drive away the chill. Unless folks remember how to manage this extra use of energy, they may be shocked when their first winter utility bills arrive or the fuel tank out back is empty before expected. Usually the garage, shop or shed is the least energy efficient space at a residence. A typical two-car garage measures 480 square feet, or about 20 percent of the size of the average U.S. home. It is often the least insulated and uses the least efficient heating systems. Yet, some are taken back in the middle of winter when keeping these areas at 50°F or higher increases their heating costs by 50% or more. Before taking up refuge in your garage this winter and cranking up the heat, consider a few of the following opportunities to keep your energy use from literally going through the roof. Insulate the walls While most people insulate their garage attics before heating them, many older homes (and even some newer ones) were not built with insulation in the walls of the garage. While most have outside siding, sheathing and a layer of particle board to keep elements out, these materials do little to retain heat. Insulating can be as easy as tacking fiberglass insulation between exposed joists. If your garage walls are finished, insulation can be blown in through a small hole in the drywall or paneling. Caulk between the walls and the concrete floor Most garages were not built using compressible foam between the lower framing and concrete floor. Over time, the framing can swell, shrink and move, leaving gaps which will allow air from the outside to leak in. You can either use a foam sealant or a latex/silicone-based caulk to seal this often-overlooked area.  Seal the door between the house and garage If your garage is attached to the house, the door leading into the home is often a major source of cold air leaking into the conditioned area. If your garage is detached, the passenger door may be letting much of your garage heat escape. Check to ensure weather-stripping is installed around the entire door frame, and that it’s intact, pliable and provides a snug seal. Also, ensure your threshold and door sweep are sealing at the bottom. Insulate the garage door Even if your garage has properly-insulated walls, you may have uninsulated garage door(s). This negates much of the benefit from insulated walls. A new, insulated door will cost several hundreds of dollars or more, but will provide a clean appearance. A lower cost solution is to purchase foam board insulation and install it on the inside panels of your existing doors. Remember, you must cut the foam board to a size a little smaller than your garage door’s panels so the insulation doesn’t smash together as the door rolls up and down. Switch to LED lighting Compared to traditional, incandescent lights, LEDs use only 10 percent of the electricity to produce identical illumination levels. Compared to fluorescent lighting, LEDs use 40 to 60 percent less energy for the same amount of light. More importantly, fluorescent lights produce less and less light as the temperature drops. Many fluorescent lights will not even operate below 10°F. In contrast, LEDs slightly increase their light output the colder it becomes. Replace older appliances If you have an older model refrigerator or freezer in your garage, it may cost more money for you to operate it over time than it would to invest into a new unit. Although the energy savings are smaller in the winter, consider how hot your garage becomes in the summer. If there is very little in the garage refrigerator or freezer, try moving items to an indoor refrigerator or freezer. Then, unplug the garage unit to save electricity. For additional ideas on how you can reduce the cost of heating your garage this winter, contact your local electric utility or visit www.energywisenebraska.com. You may even find you are eligible for EnergyWiseSM incentives for helping with the cost of other energy-saving home improvements.
October 8, 2025
It’s tempting to flip on the electric heat during the first chilly evening of autumn. If you can’t resist, keep the temperature low. The perfect thermostat setting in fall can keep you comfortable and lower your energy bills. Here’s a simple guide for September and October: Daytime: Set your thermostat between 68°F and 70°F for a cozy, energy-efficient home during the day. Nighttime: Lower the temperature to 60°F or 65°F while you sleep to save on heating costs without sacrificing comfort. When away: Set your thermostat to about 60°F if you’re out for several hours to avoid wasting energy heating an empty house. Use programmable thermostats: Automate these temperature changes to avoid manual adjustments and optimize savings. These ranges balance comfort with efficiency as outdoor temperatures cool. Adjust based on personal comfort and home insulation and consider layering clothes indoors for added warmth.
October 1, 2025
As summer fades and fall arrives, you may notice changes in your electric bill. Here’s what to expect and how to prepare: Cooling drops, heating rises: Your air conditioning use will decrease, but heating needs may start increasing, especially in late fall. Shorter daylight means more lighting: With fewer daylight hours, you’ll likely use indoor lights earlier in the evening. Switching to LED bulbs can help reduce the impact. Holiday decorating ups energy use: Halloween and early holiday lights can add to your electricity consumption. Using timers helps control costs. Appliance use shifts: You might start using appliances like ovens, space heaters or humidifiers more frequently.  Understanding these changes could help you plan and manage your energy use better.
September 24, 2025
Even as the days get shorter, making the most of natural light can reduce your energy use and brighten your home: Open curtains and blinds: Let sunlight flood your rooms during the day to reduce the need for artificial lighting. Keep windows clean: Dirty windows block sunlight. Clean the panes inside and out to maximize light penetration. Choose light-colored furniture and paint: Light walls, floors and furnishings reflect daylight, helping rooms feel brighter. Arrange furniture near windows: Place work or reading areas close to windows to take advantage of natural light.  Consider skylights or solar tubes: If possible, adding these features can bring in extra daylight year-round. Using natural daylight not only saves electricity but also improves mood and well-being. Enjoy the sunshine while it lasts.
September 22, 2025
By: NPPD Energy Efficiency Program Manager Cory Fuehrer Have you ever reminisced about how hot a summer or how cold a particular winter was? It seems to be human nature to compare current outdoor temperatures to weather we experienced in the past. One of the late Johnny Carson’s favorite ways to set up a weather joke was to start by saying, “It was so hot today…” Having seen the routine many times, his audience would boisterously reply in unison, “How hot was it?!” Obviously, his reply was the punchline to which everybody laughed. But what if there was a way to quantify how hot or cold it truly was in order to compare it to other days, months or years in the past? Actually, there is and it’s called a “degree day”. Degree days are a measurement of how cold or warm a particular location was. A degree day compares the daily mean temperature (average of the day’s high and low outdoor temperature) to a standard temperature. In the U.S., that’s usually 65° Fahrenheit (F). The more extreme the outside temperature, the higher the number of degree days. A higher amount of degree days generally results in higher energy use for space heating or cooling. More specifically, heating degree days (HDDs) are a measure of how cold the temperature was on a given day or during a period of days. For example, a winter day with a mean temperature of 30°F has 35 HDDs. Two such cold days in a row have 70 HDDs for the two-day period. If the daily mean temperature is greater than 65°F, no HDDs are associated with that particular day. On the other hand, cooling degree days (CDDs) are a measure of how hot the temperature was on a given day. If a summer day had a mean temperature of 80°F, 15 CDDs would be recorded. If the next day had a mean temperature of 85°F, 20 CDDs would be assigned to it. The total CDDs for the two days is 35 CDDs. By totaling HDDs and CDDs for entire months or years, comparisons to previous months or years can be made. Say you’d like to evaluate an average of how much energy it might take to heat and cool your home. Degree days, along with your heating and cooling system’s efficiencies and other factors can be included in this equation to provide a fairly accurate estimate. Degree days also provide possible insight as to why energy bills were higher or lower than anticipated. The Nebraska Department of Water, Energy, and Environment (NDWEE) provides historical degree day and degree day normals on a monthly basis for 12 cities around the state in addition to the state's overall average degree days. Degree day normals are 30–year averages over a baseline comparison period. Currently, NDWEE uses 1991–2020 for the baseline. Nebraska's overall HDD normal for a year is 6281. The CDD normal for a year is 996. (Note that commas are not used degree day data.) In comparison, Hawaii's HDD normal is 1 and its CDD normal is 4766. Hawaiians use almost no energy for heating but need to use huge amounts if they wish to keep indoor spaces below 80°F. In contrast, Colorado's HDD and CDD normals are 7053 and 329 respectively. While our neighbors to the west use a little more energy than us for heating, they require only about one-third of the energy to keep cool. In the 2024/2025 season, Nebraska's HDD totaled 5956, which was 325 HDD less than normal. This indicates last winter in Nebraska was about 5% warmer than normal. For the upcoming winter, the “Old Farmer's Almanac” forecasts above-normal temperatures in the Cornhusker state. By the end of next June, we should know if the prediction was right. In the meantime, when a friend claims the winter of 2018/2019 was the coldest they remember, you can prove the winter of 1978/1979 was actually the coldest in more than 50 years.  Regardless of what the upcoming winter is like, your local public power provider, in partnership with Nebraska Public Power District, may have an EnergyWiseSM incentive available when you upgrade your heating, ventilation and air conditioning system’s efficiency. Contact your local utility or visit www.energywisenebraska.com for more details.
September 18, 2025
It’s almost leaf-blowing season. Before you power up your leaf-blower and other electrical outdoor tools, check your outlets and cords for safety. Here’s how: Inspect outlets: Look for cracked or broken covers and replace any that are damaged to prevent water from getting inside and behind them. Test GFCI outlets: Outdoor outlets should be ground-fault circuit interrupters (GFCIs). Press the “test” and “reset” buttons monthly to ensure they’re working. If your home is older, contact a licensed electrician to find out if yours are GFCIs. Examine extension cords: Check cords for frays, cracks or exposed wires. Damaged cords should be replaced immediately. Use outdoor-rated cords: Only use cords labeled for outdoor use. They are designed to withstand weather conditions. Keep connections dry: Avoid plugging cords into outlets when raining or the ground is wet. Use outlet covers and keep cords elevated off wet ground. Regularly inspecting your outdoor outlets helps prevent hazards like shocks or fires. A little maintenance now can keep your fall projects safe and trouble-free.
September 12, 2025
If you want to keep the hot summer heat out of your air-conditioned home, keep the sunlight out. Close your blinds and shades, and your home will feel cooler and more comfortable. Any heat that comes in with the sunshine will compete with the cool air your central air conditioning system is pumping out, making your rooms feel hotter and tempting you to lower the thermostat. Closing curtains and other window coverings during daylight hours will save your a/c from having to work so hard, which could make it operate more efficiently and even extend its life.
August 28, 2025
Your family might use your covered outdoor porch or patio more often this summer if you keep the temperature out there cooler by installing a ceiling fan. Outdoor ceiling fans come with ratings like “damp” or “wet” that indicate what kind of climate—like humid or rainy—they can operate in safely. Never install an indoor fan on your outdoor porch; it’s not safe. Instead, choose one specifically made for outdoor use with all-weather blades, corrosion- and rust-resistant paint finishes, and a motor casing featuring a waterproof seal. Overhead fans are a great addition to a porch, sunroom or even a garage. Even in outdoor rooms with extra sunlight, a fan can circulate the air, making anyone sitting or standing nearby feels cool and comfortable.
August 20, 2025
The bathroom is one of the few places in the home where electrical appliances and water have a great chance to meet—and a great chance to cause electrical shock or death. If you have kids, the bathroom can be a room of hazards—electrical or otherwise— waiting to happen. But it doesn’t have to be. Try these tips to dampen the danger: Use a bathmat with a non-skid bottom on the floor and use a non-slip mat or decals on the floor of the tub. Keep medications and vitamins in their original containers to avoid confusion and always choose child-resistant caps. Keep medications and cleaning supplies locked away if small children are around. Make a storage space under the counter and out of the way for hair dryers, curling irons and other electrical appliances that could be hazardous with water contact. Educate children on the dangers of mixing water and electricity. Use nightlights in the hallway and bathroom for easy bathroom access at night. Don’t leave children unattended during bath time. If you have toddlers, use toilet seat locks to prevent drowning. Check the temperature of bath water and fully fill the tub before putting children in. Tap water can instantly scald if you let it run too hot. Lower the temperature on your water heater to 120 degrees Fahrenheit to guard against burns but keep bathwater at 100 degrees Fahrenheit or lower. Use only electrical appliances or cords that bear the label of an independent testing laboratory like Underwriters Laboratories.
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