Of all energy consumed in the United States, approximately one-fifth is expended on the heating and cooling, lighting, and appliances of homes. The $100 billion spent each year for household energy can be minimized, sometimes with simple changes or alterations of energy usage practices.
The largest amount of energy is used for heating and cooling houses; therefore, it is a wise economic practice to determine and correct all energy losses from your home. This can be done by conducting a home audit yourself or through a professional audit.
The Manual J Load Calculation for residential winter and summer air conditioning is a procedure used during a professional audit. This method calculates heat loss and gain in homes and determines the correct load calculation which is the primary consideration in planning and installing residential heating and air conditioning systems. The Manual J Calculation was jointly developed and adopted by the Air Conditioning Contractors of America and the Air Conditioning and Refrigeration Institute.
Homeowners also can conduct a do-it-yourself audit with a moderate amount of time and effort to correct most problem areas. These areas can be found during a careful walk-through of your home. To help prioritize problems, take notes as you carefully inspect each area.
The first determination is to discover if and where air leaks are occurring. This is one area alone that can save up to 30% in energy savings, if corrected properly. The indoor areas to check are gaps along baseboards and floor edges, and ceiling and wall junctures,. Other areas to check for drafts are window frames, electrical outlets and switch plates, weather-stripping around doors and windows, fireplace dampers, attic hatches, gaps around pipes and wires, foundation seals, and mail slots. Keep in mind that weather-stripping may need to be reapplied from time to time.
When inspecting windows and doors there are some obvious signs of leakage, such as, if they rattle or if you see daylight around their frames. Storm windows should be checked as well for breakage and fit. Windows and doors have had considerable efficiency improvements made to them in recent years and replacing old ones is often the best practice. If this, however, is not feasible, using weather-stripping and low-cost plastic sheets over windows can be very helpful.
Keep in mind that indoor air quality is also a very important issue. Although sealing openings to prevent undue loss of energy is one factor, there is also a consideration concerning "backdrafting." This happens when a home's exhaust fans and combustion appliances compete for air. Exhaust fans may pull back combustion smoke into living areas making air quality unsuitable and even unhealthy. It is important for appliances supplying heat with fuels such as natural gas, fuel oil, propane or firewood, to have an adequate amount of air. The general rule is one square inch of vent opening for each 1,000 Btu of appliance input heat. This determination should be determined by an energy professional, local utility company, or ventilation contractor.
A home's exterior should be inspected as well. Give close attention to cracks and holes in areas where two different building materials meet such as corners where brick meets with chimneys or sidings, and also at foundations. Openings around faucets, pipes, electric outlets, and wiring should be sealed with the proper material. Routine checking of the exterior caulking around doors and windows is important to maintain its effectiveness.
The insulation level in your ceiling and walls determines to a great degree the amount of heat loss in your home. The recommended minimum for your home at the time it was built may not be the current recommended amount. The amount of insulation is determined by the climate, type of heating used by the home, and the area to be insulated. The following areas should be checked:
Electricity costs for lighting account for approximately 10% of your bill. There are many factors to consider to reduce these costs; see our document Energy Efficient Lighting for detailed information.
The Alliance to Save Energy also has an excellent web site: www.ase.org.
During a professional home energy audit the auditor will conduct an examination of the outside of the house and each internal space, as well as assess past utility bills. To prepare for the audit you should do several things: 1) list existing problems or concerns you have with any part of your home, such as drafts, condensation, etc.; and 2) copy or summarize your home's energy bills for the past several years. Utility companies can provide these. The energy audit will take into consideration the structure's features such as its size, the number of windows and doors, seasonal thermostat settings, each room's amount and time of use and many other related factors.
Benefits of a professional audit include accuracy and possible immediate energy conserving measures at the time of the audit.
Professional auditors may conduct a blower door test to find a home's air infiltration rate.
A strong fan mounted into an exterior door's frame pulls air out of the house. This lowers the air pressure inside and causes higher outside air pressure to flow through all unsealed openings and cracks. This useful
information is used to correct air leakage, moisture condensation, drafts, and possible indoor air pollution problems. If you have a blower door
test, request that the auditor use a "calibrated" rather than
an "uncalibrated" door. The calibrated blower door uses several
gauges to quantify the air pulled by the fan and the air sealing effectiveness. The uncalibrated blower door locates leaks only and does not determine
the tightness of the home.
A thermographic inspection or infrared scanning test may be used to determine thermal defects and
any air leakage in your home. This is done with use of an infrared video and still cameras which see light in the heat spectrum. Thermography can determine whether or not insulation is needed or if it has been installed correctly.
If you want or need information concerning residential energy efficiency, there also are organizations which can be helpful. The Residential Energy Services Network is dedicated to the promotion of residential energy efficiency through home energy rating programs which contain financing for energy efficiency improvements. It is a broad spectrum membership national organization
comprised of various housing, consumer, and financial entities working
to promote residential energy efficiency and affordability. One of
their most important contributions to the residential energy efficiency field is the development of voluntary national guidelines to standardize home energy rating methods.
Other organizations such as the Energy Efficient Building Association (EEBA) and Affordable Comfort, Inc. should be good resources for consumers nationwide to find qualified residential energy auditors. Affordable Comfort, Inc. and the Energy Efficient Building Association promote residential efficiency through the dissemination of information and training, and both should be good sources for contacting technically reliable residential energy auditors.
There are some preliminary steps that should be taken before contracting with any company for the audit:
Contact at least three references for each company you consider. Ask about the auditor's work and the home owner's level of satisfaction.
Contact the Better Business Bureau and local utility regarding any records, complaints, etc. of the company's reputation.
Insist that the auditor use a calibrated blower door for the most accurate and effective assessment.
These precautions should allow an effective and very helpful determination of your home's energy efficiency needs. You can expect new energy efficiency procedures to contribute toward both money saved and comfort enjoyed.
* * * * *
The MEA has a quantity of booklets entitled, "ENERGY SAVERS: Tips on Saving Energy & Money at Home." If you would like a copy, e-mail DLinfo_MEA@maryland.gov or call 1-800-72-ENERGY.
1800 Washington Blvd., Suite 755, Baltimore, MD 21230
(410) 537-4000 | 1-800-72-ENERGY