Go Green! > How Energy Efficient is Your Home?
As that autumnal chill begins to creep into the September evening air, it’s time to begin buttoning up the New Hampshire home for winter. With the volatility of fuel prices and the increasing concern about climate change, investing in a professional home-energy audit can help you make informed choices.
An energy audit is a top-to-bottom analysis of your home’s energy efficiency with the goals of saving energy and money, reducing oil imports and protecting the environment. Energy audits take a whole-house approach that views your home as an energy system with interdependent parts.
According to Public Service of New Hampshire’s (PSNH’s) Your Home Energy Analysis: The First Step to More Energy-Efficient Living, 20 percent of all the energy in the United States is consumed in our homes. Even a 1 percent reduction would lead to a savings of millions of barrels of oil–not to mention reducing the pounds of carbon dioxide emissions linked to climate change.
Andy Gray directs the New Hampshire Weatherization Program, which is funded by the federal Department of Energy to assist income-eligible homeowners with energy-efficiency improvements. For homeowners considering hiring an energy audit professional, Gray recommends checking the Web site of the Residential Energy Performance Association (repa-nh.org) where a consumer guide and member profiles provide a sound starting point for finding a qualified auditor. He notes that there isn’t yet a state certification process for energy auditors.
“I encourage people to invest in an energy audit by a professional who has the proper equipment to find the leaks and weak spots in the thermal boundary,” Gray says. “Home energy audits range from $300 to $500, depending on if you want a written or verbal report, how far the auditor has to travel, the size of the house and the complexity of the information being sought.”
Energy audits also are offered at no cost by local utility companies through the collaborative NH Saves program that is funded by part of ratepayers’ monthly electric bills.
What Happens During an Energy Audit
You can schedule an energy audit at any time of the year, but a winter audit can be most telling—as long as you are not planning to do upgrades right away.
“The coldest day of the year is the best to see what improvements might be made,” says Kevin Hanlon, owner of Horizon Residential Energy Services NH, LLC in Concord. “However, the financial] savings subsequent to fuelsaving measures are delayed [with winter audits]. Energy audits can really be done at any time of the year, as auditors rely first and foremost on their eyes.”
A typical energy audit begins in the basement, one of the largest areas of heat loss. Most auditors check to see if the foundation sill (the part that meets the first floor) is insulated around the perimeter. Any exterior or bulkhead doors and windows generally will be checked for insulation and weatherstripping. The furnace and water heater are also on most checklists.
“If the basement is used as an activity area or part of the living area, we recommend insulating the walls by putting up two-by-six [boards] against the foundation wall and using six inches of R19 insulation,” say George Abood, a PSNH energy service representative with twenty-six years of experience as an auditor. (The R-value is the thermal resistance of a material to heat transfer. R-values are used to rate insulation products; the higher the R-value, the greater the insulation’s effectiveness. How insulation is installed and where it is placed also are factors that may reduce or enhance its efficacy.)
On the first level of your home, exterior door and window frames generally will be checked for air infiltration. If there is a fireplace or other heating device connected to a chimney, this also is usually inspected for air leakage.
Two tests are available that provide the best gauge of how well your home uses its heating or cooling capacity. Public-utility energy auditors offer these tests if your home meets electric heat qualifications, and a private auditor usually will suggest them:
¦ The blower-door diagnostic test evaluates your home for air leakages and cool spots in the exterior walls.
¦ Infrared camera imaging may be applied at the same time to show the variety of surface temperatures. It shows if insulation is missing or has settled. Colder areas will appear blue on the screen, providing a visual picture of how the house is functioning.
These tests—along with knowing the year your house was built—provide information about exterior wall construction.
“If insulation is needed, we recommend having it blown in, which is usually cellulose,” says Abood. “It has a higher R-value per inch than Fiberglas®. A new state building code went into effect in the mid-eighties that improved insulation and wall construction requirements.”
Managing the attic for efficiency requires proper ventilation from some combination of soffit, ridge or gable vents along with insulation on the attic floor.Venting the attic controls moisture buildup in the home and reduces the opportunity for mold to form. Soffi t vents help to prevent ice dams on the roof.
“The attic should be the same as the outside temperature,” Abood says. “Insulating between the living area and the attic will keep the living space cooler in the summer and minimize heat loss in the winter.” To minimize heat loss into the attic, PSNH recommends twelve inches of R38 insulation for attic fl oors–a step above the state requirement of ten inches of R30.
“I’m often at a house three to four hours,” Hanlon says. “A professional opens every hatch—attic, basement, closets. It’s quite a puzzle a lot of the time. Most New England homes have architectural features—like lookouts, dormers and additions—that can pose weatherization problems. Our goal is improved comfort, better durability and indoor air quality along with fuel reduction.”
Using The Information the Audit Uncovers
Take good notes during your energy audit, even if you are paying for a written report. Ask the auditor if you may make a recording of his or her comments for later reference. Once the audit is completed and all the information compiled, it’s time to take action and plan your energy-efficiency upgrades. Check with your auditor to see if you might qualify for any of the federal, state or local utility programs available for assisting with home-energy-efficiency improvements.
Our homes are a synergistic combination of many factors that are fine tuned to our personal comfort requirements: building materials; life support systems, such as fuel and water; architectural elements; and the people (and pets) who live there. When all these systems work at peak efficiency, your investment in an energy audit will likely save energy costs and reduce the human effect on our planet.