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Home Energy Audits A home energy audit is the first step to assess your home's energy diet, and to evaluate what measures you can take to make your home more energy-efficient. An audit will show you problems that may, when corrected, save you significant amounts of money over time. During the audit, you can pinpoint where your house is losing energy. Audits also determine the efficiency of your home's heating and cooling systems. An audit may also show you ways to conserve hot water. You can perform a simple energy audit yourself, or have a professional energy auditor carry out a more thorough audit. A professional auditor uses a variety of techniques and equipment to determine the energy efficiency of a structure. Thorough audits often utilize equipment such as blower doors, which measure the leakiness of the building envelope, as well as infrared cameras, which reveal hard-to-detect areas of air infiltration and missing insulation. The following is a discussion of do-it-yourself as well as professional audits. Do-It-Yourself Audits You can easily conduct a home energy audit yourself. With a simple, but diligent, "walk-through," you can spot many problems with any type of house. When auditing your home, keep a checklist of areas you have inspected and problems found. This will help you prioritize your energy efficiency upgrades. Locating Air Leaks First, make a list of obvious air leaks (drafts). The potential savings in fuel from draft reduction may range from 5% to 30% per year, and the home is generally much more comfortable afterwards. Check for indoor air leaks such as gaps along the baseboard or edge of the flooring, and at junctures of the walls and ceiling. Check to see if air can flow through electrical outlets, switch plates, window frames, baseboards, weather-stripping around doors, fireplace dampers, attic hatches, and wall- or window-mounted air conditioners. Look for gaps around pipes and wires, electrical outlets, foundation seals, and mail slots. Check to see if the caulking and weatherstripping are applied properly (no gaps or cracks), and are in good condition. Inspect windows and doors for air leaks. See if you can rattle them, since movement means possible air leaks. If you can see daylight around door and window frames, then the door or window leaks. You can usually seal these leaks by caulking or weatherstripping them. Check the storm windows to see if they fit and are not broken. You may also wish to consider replacing your old windows and doors with newer, high-performance ones. If new factory-made doors or windows are too costly, you can install low-cost plastic sheets over the windows. If you are having difficulty locating leaks, you may want to conduct a basic building pressurization test. First, close all the exterior doors, windows, and fireplace flues. Turn off all combustion appliances such as gas burning furnaces and water heaters. (Remember to turn them back on when you are done with the test.) Then turn on all exhaust fans (generally located in the kitchen and bathrooms) or use a large window fan to suck the air out of the rooms. This increases infiltration through cracks and leaks, making them easier to detect. You can use incense sticks or your damp hand to locate these leaks. Moving air causes the smoke to waver, and you will feel a draft when it cools your hand. CAUTION: When sealing any home, you must always be aware of the dangers of indoor air pollution and combustion appliance "backdrafting." In homes where a fuel is burned (i.e., natural gas, fuel oil, propane, firewood) for heating, be certain the appliance has an adequate air supply. Generally one square inch of vent opening is required for each 1,000 Btu of appliance input heat. When in doubt, contact Guam Power Authority, Guam Energy Office, energy professional, or ventilation contractor. On the outside of your house, inspect all areas where two different building materials meet. You should plug and caulk holes or penetrations for faucets, pipes, electric outlets, and wiring. Look for cracks and holes in the mortar, foundation, and siding, and seal them with the appropriate material. Check the exterior caulking around doors and windows, and see whether exterior storm doors and primary doors seal tightly. Insulation Heat loss through the ceiling and walls in your home could be very large if the insulation levels are less than the recommended minimum. You should check to see if the level of the roof and wall insulation of your home is at least at the minimum recommended amount. When your house was built, the insulation recommended at that time was installed. Given today's energy prices, and that future prices probably will be higher, the level might be inadequate, especially if you have an older home. Never cover recessed light fixtures with insulation, however. To avoid fire hazards, allow a three-inch space around these fixtures, unless the fixture is IC rated (insulation covered). While you are inspecting the roof above the rafters, check to see if there is a vapor barrier (retarder) under the insulation. The vapor barrier might be tar paper, kraft paper attached to fiberglass batts, or a plastic sheet. If there does not appear to be one, you may want to consider painting the interior ceilings with vapor barrier paint. This reduces the amount of water vapor that can pass through the ceiling. Moisture can reduce the effectiveness of insulation and promote structural damage. Make sure that the roof vents are not blocked by insulation. You also should seal any electrical boxes in the ceiling (from the inside) with flexible caulk and then cover them with the recommended amount of insulation. Please refer to the previous paragraph concerning recessed lighting. Checking a wall's insulation level is more difficult. Select an exterior wall and turn off the circuit breaker or unscrew the fuse for any outlets in the wall. Be sure to test the outlet to make certain that it is not "hot." You can do this by plugging a lamp or portable radio into the outlet. If you can turn it on, then you switched off the wrong breaker. Remove the cover plate from one of the outlets and gently probe the wall with a thin, long stick or screwdriver. If you encounter a slight resistance, you have some insulation there. You could also make a small hole in a closet, behind a couch, or in some other unobtrusive place to see what, if anything, the cavity is filled with. Ideally, the wall cavity should be totally filled with some form of insulation material. Unfortunately, this method cannot tell you if the entire wall is insulated, or if the insulation has settled. Only a thermographic scan (discussed below) can do this. If your basement is unheated, determine whether there is insulation under the living area flooring. In most areas of the country, R-25 is the recommended minimum level of insulation. The insulation at the top of the foundation wall and first floor perimeter should have an R-value of 19 or greater. If the basement is heated, the foundation walls should be insulated to at least R-19. Your water heater, hot water pipes, and furnace ducts should all be insulated. Heating/Cooling Equipment Inspect heating and cooling equipment annually, or as recommended by the manufacturer. If you have a forced air furnace, check and replace your filters as needed. Generally they should be changed about once every month or two, especially during periods of high usage. Have a professional check and clean your equipment once a year. If the unit is more than 15 years old, you should consider replacing it with one of the newer, energy- efficient units. This would go far to reduce your energy consumption, especially if the existing equipment is in poor condition. Check your duct work for dirt streaks, especially near seams. These indicate air leaks, and they should be sealed with metal-backed duct tape or a duct mastic. Insulate any ducts or pipes that travel through unheated spaces. An insulation R-value of 6 is the recommended minimum. Lighting Energy for lighting accounts for about 10% of your electric bill. Examine the wattage size of the light bulbs in your house. You may have 100 watt (or larger) bulbs where 60 or 75 watts would do. You should also consider compact fluorescent lamps for areas where lights are on for hours at a time. Your electric utility may offer rebates or other incentives for purchasing energy-efficient lamps. EREC has additional information about energy-efficient lighting. Professional Energy Audits Most professional energy audits include a "walk-through" like the one above. The professional audit, however, will generally go into much greater detail. The auditor will do a room-by-room examination of a residence, as well as a thorough examination of past utility bills. Before the auditor visits your house, make a list of any existing problems such as condensation and uncomfortable or drafty rooms. Have copies or a summary of the home's yearly energy bills. (Your utility can get you these.) The auditors use this information to establish what to look for during the audit. The auditor first examines the outside of the home to determine the size of the house and its features (i.e., number and size of windows). The auditor then analyses the occupants' behavior: Is anyone home during working hours? What is the average thermostat setting for summer and winter? How many people live here? Is every room in use? Your answers may help uncover some simple ways to reduce your household's energy consumption. Walk through your home with the auditors as they work, and ask questions. They may also use equipment to detect sources of energy loss, such as blower doors, infrared cameras, furnace efficiency meters, and surface thermometers. Blower Door Tests A blower door is a powerful fan that mounts into the frame of an exterior door. The fan pulls air out of the house, lowering the air pressure inside. The higher outside air pressure then flows in through all unsealed cracks and openings. The auditors may use a smoke pencil to detect air leaks. These tests determine the air infiltration rate of a building. Several reasons for establishing the proper building tightness are: to reduce energy consumption due to air leakage, to avoid moisture condensation problems, to avoid uncomfortable drafts caused by cold air leaking in from the outdoors, and to make sure that the home's air quality is not too contaminated by indoor air pollution. There are two types of blower doors: "calibrated" and "uncalibrated". It is important that auditors use a calibrated door. This type of blower door has several gauges that measure the amount of air pulled out of the house by the fan. Uncalibrated blower doors can only locate leaks in homes. They provide no method for determining the tightness of a building. The calibrated blower door's data allows the auditor to quantify the amount of air leakage and the effectiveness of any air-sealing job. Thermographic Inspection Energy auditors may also use thermography—"infrared scanning" to detect thermal defects and air leakage in building envelopes. Thermography measures surface temperatures by using infrared video and still cameras. These tools see light that is in the heat spectrum. Images on the video or film record the temperature variations of the building's skin, ranging from white for warm regions to black for cooler areas. The resulting images help the auditor determine whether insulation is needed. They also serve as a quality control tool, to ensure that insulation has been installed correctly. A thermographic inspection is either an interior or exterior survey. The auditor decides which method would give the best results under certain weather conditions. Interior scans are more common, because warm air escaping from a building does not always move through the walls in a straight line. Heat loss detected in one area of the outside wall might originate at some other location on the inside of the wall. Also, it is harder to detect temperature differences on the outside surface of the building during windy weather. Because of this, interior surveys are generally more accurate, as they benefit from reduced air movement. Besides their accuracy, another advantage of professional audits is that they can carry out some energy-conserving measures at the time of the audit, so your payback begins immediately. A house call consisting of a four to eight hour audit and follow-up retrofit work costs (depending on the amount of work needed) around $300 to $500. Finding and Selecting an Energy Auditor There are several places where you can locate professional energy auditing services. Your state or local government energy or weatherization office may help you identify a local company or organization that performs audits. They may also have information on how to do your own audit. Your electric or gas utility may conduct limited residential energy audits, or recommend local auditors. Selecting any type of contractor requires some effort and planning. Before contracting with an energy auditing company, you should take the following steps: 1. Get at least three references, and contact all three. Ask if they were satisfied with the auditor's work. 2. Call the local utility and Better Business Bureau and ask for any records or opinions on the company's reputation. 3. Make sure the auditor uses a calibrated blower door, as this is the best way to measure the effectiveness of any work they perform. 4. Make sure that they conduct thermographic inspections, or contract with another company to conduct one. Bibliography The following are good sources of information on how to reduce the amount of energy you use at home, and how to keep energy costs down. Some of them provide tips on home energy auditing, and/or on how to prioritize your energy efficiency investments. The publications may be found in your local bookstore, library, or obtained from the publisher as indicated. You should verify availability, prices, and shipping charges before ordering from the publisher. This bibliography was updated in February, 1996. Articles "Energy-Saving Roundup," Consumer Reports, (58:10) pp. 649-67, October 1993. "Energy-Saving Heating Tips," J. Wasik, Consumers Digest, (31:33) September/October 1992. "Guide to Saving Energy in Your Home," Country Living, (13:55) September 1990. "Improving Your Heating System's Efficiency," Consumers' Research Magazine, (74:23) pp. 23-25, December 1991. "What to Know About a Home Energy Audit," Consumers' Research Magazine, (73:19) pp. 17-21, January 1990. Books Consumer Guide to Home Energy Savings, A. Wilson, American Council for an Energy-Efficient Economy (ACEEE), 1995. Available from ACEEE, 2140 Shattuck Avenue, Suite 202, Berkeley, CA 94704, (510) 549-9914. 265 pp., $7.95. Energy: 101 Practical Tips for Home and Work, S. Hassol and B. Richman, Windstar Foundation, 1989. Available from Windstar Foundation, 2317 Snowmass Creek Road, Snowmass, CO 81654, (303) 927-4777. 96 pp., $3.95. Energy Alternatives, Home Repair and Improvement Series, Time-Life Books, 1992. Available from Time-Life Books, 1450 East Parham Road, Richmond, VA 23280, (804) 266-6330. 136 pp., $11.99. Five Hundred Forty-Seven Tips for Saving Energy in Your Home, R. Albright, Storey Communications, 1992. Available from Storey Communications, Schoolhouse Road, Pownal, VT 05261, (800) 441-5700. 128 pp., $7.95. Home-Made Money: How to Save Energy and Dollars in Your Home, R. Heede, et al., Rocky Mountain Institute (RMI), 1995. Available from RMI, 1739 Snowmass Creek Rd., Snowmass, CO 81654-9199, (970) 927-3851. 276 pp., $14.95. How to Make Easy Money Auditing Your Home Utility Bills, L. Etherington, UAS Publications, Phoenix, AZ. 1992, 144 pp. Print status undetermined, contact local book store or library. Warm House—Cool House: A Money-Saving Guide to Energy Use in Your Home, M. Florman and Consumer Reports Books Editors, Consumer Reports Books, Fairfield, OH, 1991. 208 pp. Out of print. Periodicals Consumer Reports, The Consumers Union of the United States, Inc., 101 Truman Avenue, Yonkers, NY 10703, (800) 234-1645 (subscriptions and back issues). Published monthly. $22.00/yr. This magazine often evaluates major home appliances, and the energy consumption of the appliance is one of the areas examined. Consumer's Research Magazine, Consumer's Research Inc., 800 Maryland Avenue, NE, Washington, DC 20002, (202) 546-1713. Published monthly. $21.00/year. This magazine often features articles on residential appliances. Home Energy, 2124 Kittredge Street, No. 95, Berkeley, CA 94704. Published bimonthly. $49.00/year. Articles on residential energy efficiency products, technologies, and programs are published in each issue of this journal. Home Mechanix, P.O. Box 54320, Boulder, CO 80322-4320. Published ten times per year. $13.94/year. General overviews on residential energy technologies are often provided in Home Mechanix. Specific products are frequently highlighted. Practical Homeowner, P.O. Box 58977, Boulder, CO 80322-8977. Published nine times per year. $13.97/year. Home maintenance is the primary focus of this journal, and frequent articles on home energy efficiency are featured. Videos 10 Quick Waysto Cut Your Energy Bills, Iris Communications, Inc., 1994. Available from Iris Communications, 258 East 10th Avenue, Suite E, Eugene, OR 97401-3284, (800) 346-0104. 20-minute video tape, $20.00. http://www.guampowerauthority.com/news/energycon-homeaudit.html