Today’s Energy-Efficient Home
By Andy Sinclair. Previously published in the 2016 Winter Issue.
Whether Tudor, Colonial, log cabin, Cape Cod, bungalow, Craftsman, A-frame, ranch, Pueblo, bi-level, split level, farmhouse, townhouse, cottage, Adirondack, rammed earth, or geodesic, today’s home can (must) be energy-efficient. In today’s economy, you literally cannot afford to have an energy-inefficient home.
What exactly is an energy-efficient home? Some home builders construct homes with 2×6-inch wood studs in the exterior walls rather than 2x4s to increase wall insulation, while others may provide buyers with the option of installing ENERGY STAR© qualified appliances. All of these methods contribute to making a home energy-efficient, but they are each just one part of the energy-efficient home.
A home is an interoperating system. Its components include the furnace and air conditioner, windows and doors, wall and ceiling insulation, plumbing and water heaters, electric wiring and electronics, appliances, home furnishings and the occupants—both people and pets.
Think of your last Thanksgiving dinner. While preparing to cook the turkey and make pumpkin pies, you use hot water, as well as the oven and range, where heat is generated. The home is being heated by the furnace or heat pump. Your insulation performs its job well by keeping all of this heat within the home. To reduce the increasing heat, a kitchen window is opened, or worse yet, the air conditioner is turned on. Now you’re both heating and cooling the home simultaneously.
On Thanksgiving Day, or on any given day, multiple systems are working together in concert, or at times, against each other. An energy-efficient home is designed to manage these interoperating systems.
Home builders today have a much better understanding of homes operating as systems. Energy-efficient home builders incorporate building science into their homes. Building science is generally described as scientific knowledge and experience focused on analyzing and controlling physical building and architectural properties. It may include the interaction between building materials, HVAC (heating, ventilating, and air conditioning) systems, lighting, and insulation, as well as other components.
The U.S. Energy Information Administration’s (EIA) most recent Residential Energy Consumption Survey released in 2013 shows that U.S. homes built in 2000 and later consume only two percent more energy on average than homes built prior to 2000, despite being on average 30 percent larger. Reasons for the lack of a significant increase in consumption include building science and energy efficiency.
There are a number of energy-efficient home brands and certifications that incorporate building science. ENERGY STAR certified homes is one such brand. According to the U.S. Environmental Protection Agency (EPA), “ENERGY STAR-certified new homes are designed and built to standards well above most other homes on the market today, delivering energy efficiency savings of up to 30 percent when compared to typical new homes.”
“A new home that has earned the ENERGY STAR label has undergone a process of inspections, testing, and verification to meet strict requirements set by the EPA, delivering better quality, better comfort, and better durability.” Home energy raters, that is, certified energy efficiency home inspectors, work with ENERGY STAR home builders throughout the construction process.
Raters conduct a series of inspections to ensure homes contain appropriate energy-efficient features for specific climate regions. Inspections are conducted for the following areas and systems:
•Building shell: walls, floors, ceilings, windows, doors, and insulation, in addition to a blower-door test to verify air sealing requirements to prevent leaks and drafts
•HVAC system: to assure the system’s design and installation provides optimal performance and comfort
•Lighting and appliances: ENERGY STAR-qualified light fixtures and bulbs, and appliances including refrigerators, clothes washers, and dishwashers
•Water management: related to water and moisture to protect the roof, walls, and foundation
After deciding to build an ENERGY STAR-certified home, it’s time to consider financing. ENERGY STAR can assist with that. Banks and mortgage companies across the country offer Energy Efficiency Mortgages (EEM).
“An EEM is a mortgage that credits a home’s energy efficiency in the mortgage itself. EEMs give borrowers the opportunity to finance cost-effective, energy-saving measures as part of a single mortgage and stretch debt-to-income qualifying ratios on loans, thereby allowing borrowers to qualify for a larger loan amount and a better, more energy-efficient home,” according to ENERGY STAR. New home EEMs are sponsored by the Federal Housing Administration, a federally insured mortgage program, and the conventional secondary mortgage market.
The Well-Insulated Home
Energy efficiency can be incorporated at various stages of the new home process. Insulation, that fuzzy stuff, is added to the bare bones, or wood studs.
Insulation is measured in R-values. Wall insulation R-values range between R-11 and R-19 depending on whether walls are constructed with 2×4 or 2×6 wall studs respectively. Ceiling insulation R-values vary greatly depending on your climate. If you live in New Orleans, your ceiling R-value may be R-30. While the R-value for a home in Minneapolis may be R-49. These are minimum ENERGY STAR certified home recommendations.
Spray-on cellulose insulation is an innovative energy efficiency measure that greatly reduces heat loss and gain, as well as reducing air infiltration into the home. As opposed to batt insulation that leaves gaps around irregular wood studs, pipes, and wiring, spray-on insulation fills the gaps, resulting in greater comfort and efficiency.
Water heating is the second largest user of home energy, just behind heating. Water heating comprises approximately 18 percent of the utility bill, while heating represents 42 percent, according to the U.S. Energy Information Administration.
There are several ways to be energy-efficient with water heating. First, choose an efficient model of water heater that is large enough to meet your needs. Water heating efficiency is measured in Energy Factors (EF). The greater the EF, the more efficient the water heater and the more energy and money it will save.
Gas storage type ENERGY STAR qualified models have a minimum EF of 0.67, while electric storage type ENERGY STAR-qualified models have a minimum EF of 2.0.
Today’s highly efficient instantaneous or tankless water heaters heat water instantly, and only when you need it. With a tankless model, there is no longer any need to store hot water, resulting in less heat being lost to unheated garages and basements.
According to appliance industry data, home appliance energy efficiency has improved 70 percent since 1972.
Today’s ENERGY STAR certified clothes washers are much more efficient than models manufactured just 10 years ago, and today’s non-certified standard models. ENERGY STAR states: “If you have a standard clothes washer that is over 10 years old, it’s costing you, on average, $180 a year.” On the other hand, “ENERGY STAR-certified clothes washers use about 25 percent less energy and 40 percent less water than standard washers.”
Add a dishwasher to your energy-efficient home and stop hand-washing dishes. It’s both efficient and economical. Hand-washing dishes costs approximately $40 more per year than using an ENERGY STAR-certified dishwasher. “A new qualified dishwasher uses less than half as much energy as washing dishes by hand and saves nearly 5,000 gallons of water a year,” according to ENERGY STAR.
By using an ENERGY STAR qualified dishwasher, you can also save approximately 230 hours per year. Imagine what you can do with nearly 10 days of free time.
Just how energy-efficient do you want to be? Do you want more “green” in your life? These are complicated questions, with a multitude of answers.
There are numerous ways to have an energy-efficient home today. Your energy-efficient home can and should be safe, comfortable, and livable. Above all, you want your home to be a reflection of you.