You can lock in long-term savings on utility bills by working on tactical energy-efficient upgrades for your home, particularly by beefing up the insulation and air-sealing to improve retention of treated air. These improvements require up-front investment, but if you’re smart about where you put your money you can realize substantial gains over time. Read on for tips on how to make your home energy-efficient and an example of how putting $1,000 into a typical American home can pay for itself in energy savings.
How Much is Your Average Electric Bill?
Utility bills will widely among houses, depending on a number of factors, most notably your geographic location and the size of your home. For our exercise, we’ll take the example of a 1980 ranch with 1,500 sq. ft of living space. Our home has an attic with soffits and gable venting and for insulation, 3 inches of R-10 cellulose in the attic and R-13 fiberglass in the walls. There are 1 1/2 baths and a natural gas stove in the kitchen. In the unfinished basement, we have a 10-year-old electric tank-style water heater and a newer natural gas furnace and central air system. We’ll say the home has an average monthly electric bill of 920 kWh used at 11.26¢ per kWh, for a total of $103.67 monthly or $1244.04 yearly.
Note that our model home is considerably smaller than the average square footage for new US homes in 2010, which was 2,300 square feet, compared to 1700 sq. ft. in 1973 and 900 sq. ft. in 1950. So if you live in a newer home, your expenses might be significantly higher, although some of that could be offset by more modern insulation and appliances.
Improve Your Insulation
The biggest impact you can make on your energy efficiency is by preventing hot and cold air from leaking out, as 50 to 70 percent of energy in the average American home goes into heating and cooling, according to the US Department of Energy. Adding more insulation and air sealing your home can save up to 20 percent of heating and cooling costs, especially if you live in an older, drafty home. In our demo house, that 20 percent could add up to $14 each month or $168 per year.
We’re going to focus our insulation intervention on the attic, where it works like a blanket to stabilize indoor temperatures. Most homes are built with under-insulated attics compared to the Department of Energy minimum recommendation of R-30 insulation, specifying its resistance to heat conduction. If our home has a lowly R-10 layer of insulation in the attic, we’ll need to add R-20, or six inches, to achieve the minimum. The most common attic insulation materials are cellulose or fiberglass, for which prices will vary depending on what brand you choose and where you purchase it. For our exercise, we’re going to buy 46 bags of blown cellulose insulation at $6 per bag.
Our price is $276.
If we purchase 31 rolls of R-19 fiberglass to do the job instead, it would cost around $300. As an added bonus, you can deduct 10 percent of the amount you spend on insulation (up to $500) from your federal income taxes.
Search Out and Fill the Leaks in Your Walls
Once your insulation is up to par, it’s time to track down the drafts in your house and seal the leaks, which are responsible for up to 40 percent of your heating and cooling load. Follow these steps to conduct a building pressure test and discover the openings where air is getting in or out of your house:
- Close all exterior doors, windows, and fireplace flues.
- Turn off all combustion appliances (gas burning furnaces and water heaters).
- Turn on all exhaust fans (kitchen and bathrooms) or use a large window fan to blow the air outside.
- Carry a lit stick of incense around the interior of your home and keep an eye on areas where the smoke appears to be drawn to, then disappears into, the wall.
You can plug any air leaks you find with caulk or expanding foam, while weather stripping will solve most problems with doors and windows.
The materials we need for air sealing will set us back $200.
Seal Your Ductwork
Another place you can lose your treated air is in the ductwork for your HVAC system, which must be tightly sealed to circulate air with optimal energy efficiency. Leaks, holes and poorly connected ducts can result in the loss of 20 percent or more of conditioned air, which is another wasted $14 per month in our home.
There are a variety of materials available to help seal up your ductwork:
- Aluminum duct tape. Aluminum duct tape is better suited for connecting duct sections and plugging holes than vinyl duct tape.
- Ductwork mastic. This caulk-like material fills and seals seams and can be applied over aluminum duct tape.
- Ductwork insulation. Apply to sealed ductwork to keep the air at the proper temperature as it blows through the duct.
While mastic and tape are cheap ($25 total for both), R-6 duct insulation will run about $250.
We’ll be spending $275 to seal ductwork.
Ventilate the Attic
Hot air trapped in your attic can put a big strain on your air conditioner, sending your energy costs soaring to battle temperatures that can climb above 120°F in the summer. To cool the attic, heated air flows out of the gable vents at either end of the roof while soffit vents under the eaves let cool air in. Newer homes do a better job using ridge vents that run along the peak of the roof to let hot air escape. Retrofitting ridge vents onto an older home is easy but it does require cutting a long slot through the roof’s peak. For our home, we’ll install five 10-foot aluminum ridge vents for $10 apiece.
Attic ventilation will cost $100 total.
Insulate Your Hot Water Heater
Heating water accounts for 18 percent of your home’s energy bill, which comes to $18.67 per month and $224.04 per year in our demo home. Most homes use a storage tank water heater to keep hot water ready even when nobody’s home to use it, and the tanks and pipes are frequently under-insulated. Wrap a water heater blanket (or “jacket”) around the tank and place foam pipe insulation on the hot water pipes for an inexpensive fit that is easy to install.
Hot water insulation will cost us $40.
Find Your Ideal Temperature With a Programmable Thermostat
If you can find 8 hours a day to turn your thermostat back by 7 to 10 degrees, you can reduce your heating and cooling costs by as much as 10 percent, according to EnergySavers.gov. Natural times to make the adjustment are at night, or during the day when everyone is at work or school. An easy way to ensure you are capturing that savings, which amounts to $7 per month or $84 per year for our demo home, is by purchasing a programmable thermostat so you can set it and forget it. You can find a decent model for under $70.
We pay $70 for a new programmable thermostat.
Use LED Bulbs
There’s probably a room or two in your house where the lights are on almost constantly. Let’s make an example of a three-bulb pendant light over the dining table that’s on for 10 hours a day. Its three incandescent 60-watt bulbs total 180 watts, which over ten hours consume 1.8 kWh of electricity. With our rate of 11.26¢ per kWh that adds up to 20.26¢ per day, which doesn’t sound like much until you tally it out to $6.08 per month and $72.93 per year. That’s just for electricity – since incandescent bulbs give off lots of heat and burn out often, there are also the extra work for the AC and replacement costs to take into account.
Compare that to an 8-Watt LED bulb, which can last up to 50 times as long as an incandescent while producing light for little energy and hardly any heat. Three 8-watt LED bulbs will use 24 watts, or just .24 kWh over a 10-hour day of use. That comes out to 2.7¢ per day, 81¢ per month, and a mere $9.72 per year, saving $63.21 each year versus standard incandescent bulbs.
We’re buying 3 dimmable LED bulbs for $20.00, leaving us with $19 of our original $1000 to devote to miscellaneous hardware expenses.
The Final Tally
When all is said and done, we’ve spent $1,000 on our house and cut perhaps $600 from our yearly utility bills with these easy ways to make your home more energy-efficient. That’s a reduction of 50 percent, enough to get your money back in under two years. Talk about a serious return on investment, before you even take into account opportunities for tax credits for energy-efficient upgrades, which can help your dollars stretch even further.
The best part is, these are just a few examples of energy-efficient upgrades – there are a wealth of other opportunities to improve the integrity of your home and maximize your heating and cooling budget. Whether you make a major push or tackle little jobs here and there, every little bit helps for bringing out the very best in your house.