Frequently Asked Questions

Space Heating - General

Q. What is the most efficient thermostat setting for heating?

A. The best setting is the lowest temperature at which you are comfortable. Most people can be comfortable at a setting of 68 - 70° - each degree higher than that can increase your heating costs by 1- 3%.

Q. I've heard that setting back my heat can actually cost me more when I turn the thermostat back up - is this true?

A. With most heating systems, you will save by turning the thermostat back for four hours or more. If you have a heat pump, you should either set the thermostat at a comfortable temperature and leave it, or use a programmable thermostat specifically designed for a heat pump.

Q. How often should I change the filters in my forced air heating or air conditioning system?

A. You should check your filters on a regular basis (monthly checks are recommended), and replace them whenever they appear dirty. A dirty filter can interfere with the proper air flow through the system, making it work harder and increasing operating costs.

Q. How often should I have my heating system serviced?

A. Any central heating system should be checked by a qualified service person once a year. Annual maintenance can extend the life of the system while also maintaining optimum efficiency.

Q. I've seen furnaces and air conditioners rated in terms of BTUs. What is a BTU?

A. A BTU or British Thermal Unit is a unit of heat. One BTU is roughly equivalent to the amount of heat produced by a single kitchen match burning completely.

Q. What is a "dual fuel" system, and how does it work?

A. Dual fuel systems can switch between two different fuels or energy sources, typically gas and electricity. The most common type combines an electric heat pump with a gas furnace. The heat pump provides heating during milder weather when it is most efficient, and the gas furnace takes over in colder weather when it is most efficient.

Q. I've been using my fireplace to heat my house, but my (electric/gas) bills have not gone down. Why is this?

A. Most fireplaces are not very efficient at heating the home, because they draw a great deal of heated air up the chimney from inside the home. Consider installing a set of glass doors which will limit the amount of air drawn up the chimney while allowing the heat to radiate into the room.

Q. If my power goes out, is it safe to run my oven with the door open for heat?

A. Using a stove or oven for heat is NOT recommended. If the stove or oven is electric, the exposed elements can be a safety hazard, and if the stove or oven is gas, the unvented combustion byproducts can be a health hazard. The safest thing to do is keep all doors and windows closed and bundle up until the power is back on.

Q. I've heard a lot lately about duct cleaning services - should I have this done?

A. Unless you are experiencing indoor air quality problems, it is probably not necessary. If you do feel that it's necessary, be sure to use a qualified, reputable contractor.

Q. Should I open the heating registers in the ductwork in my basement to keep my water pipes from freezing in winter?

A. Unless your basement ceiling is insulated, there is probably enough heat loss from the upstairs into the basement to keep pipes from freezing. If your pipes are exposed to cold air leaking in around the perimeter of the basement, you should seal any places where cold air is getting in and insulate the pipes. This should keep them from freezing without the need to intentionally heat the basement.

Q. What about using "heat tape" to keep my pipes from freezing in winter?

A. The best option is to make sure the pipes are insulated and any sources of outside air infiltration sealed. When pipes freeze, it is usually due to exposure to cold outside air. If the pipes cannot be adequately protected, "heat tape" (a tape-like material with a thin electric wire which produces heat) should be used only with caution - there have been cases of fires started by faulty or damaged heat tape.

Q. Is it a good idea to close or seal off the heating registers in unused rooms?

A. Closing or sealing a small number of heating registers may cut your heating bills some, but with central forced air systems, closing off more than one-third of your registers can create pressure imbalances and make the blower fan work harder, potentially shortening equipment life.

Space Heating - Electric

Q. What is the most efficient way to use electric baseboard heating?

A. Electric baseboard heating typically has a separate thermostat in each room. With this type of system, you should heat the room you are in to a comfortable temperature (typically 68 - 70°), and set unoccupied rooms back to 55 - 60°, keeping interior doors closed.

Q. My home is heated with an electric furnace and it can be quite costly - what are my replacement options?

A. Either an electric heat pump or a natural gas furnace will be less costly to operate. Ask your heating contractor to assess the current system and recommend which would be the simplest and most cost-effective replacement.

Q. What is the "auxiliary" or "emergency" heat switch on my heat pump thermostat? How does it affect my heating bills?

A. Most heat pumps are supplemented by electric resistance heating elements, which provide additional heat in very cold weather and "emergency" heating if the heat pump's compressor malfunctions. The supplemental heat comes on automatically when the heat pump is unable to meet the heating demand, while the emergency heat is switched on manually. Excessive use of this supplemental or emergency heat can increase heating costs significantly. Most heat pump thermostats have a small light that indicates when the supplemental or emergency heat is operating.

Q. If I have a heat pump, should I set my heat back at night or when I'm away during the day?

A. If your heat pump system is equipped with a programmable thermostat, temperature setbacks can save on heating costs. Manual setbacks are not recommended - when you turn the temperature back up, you could be causing the electric resistance back-up elements to turn on, increasing your costs. .

Q. What is a "geothermal" heating system?

A. Geothermal means "heat from the earth". A geothermal system is a heat pump that absorbs heat from either the ground or from water pumped from a well or pond. Both the ground and ground water tend to be warmer in the winter than outdoor air, enabling the system to operate more efficiently and less expensively.

Q. What is a "thermal storage" heating system?

A. Thermal storage systems are designed to take advantage of "time of use" rates, which are lower during "off peak" hours (times of lower demand). They typically use electricity to produce heat during off-peak hours , and incorporate some type of storage medium (stone, masonry or ceramic materials) to store the heat until it is needed. When the thermostat calls for heat, the fan blows air across or through the storage medium and then through the home's duct system.

Q. Can thermal storage heating be used in combination with a heat pump?

A. An electric thermal storage system can be a good supplement to a heat pump if you are on a "time of use" rate. When the heat pump is unable to meet the heating demands of the home, electric resistance heating is typically used for supplemental heat, which can increase operating costs significantly. By using electric thermal storage for the supplemental heat, the cost of supplemental heating can be reduced, thereby reducing overall operating costs.

Q. What is a "radiant" electric heating system?

A. An electric radiant heating system typically uses specially designed ceiling panels, with built-in low-powered electric heating elements. The heat is "radiated" downward into the room, in much the same way that the sun's heat warms the earth. Like sunlight, radiant heat works by "line of sight", meaning that it can be blocked by furniture or other obstructions. With careful furniture placement and proper system design, this can be a very even, comfortable type of heating.

Space Heating - Gas

Q. I'm about to replace my furnace and have noticed that, on very cold days, it seems to run constantly. Should I get a larger unit?

A. A gas furnace is most efficient when it runs for long periods of time (much as your car gets better gas mileage on the highway). A properly sized furnace should run almost constantly on very cold days. As long as the furnace is capable of maintaining a comfortable temperature, you probably don't need a larger one.

Q. What is the definition of the term "AFUE"?

A. AFUE or "Annual Fuel Utilization Efficiency" is a measure of how efficient the furnace is over an entire heating season. The higher the number, the more useable heat you will get for every unit of fuel. A furnace with an AFUE of 80% will provide 80 cents worth of heat for every dollar of fuel.

Q. Should I turn off the pilot light on my furnace during the summer?

A. The pilot light on a furnace can use several dollars worth of gas each month, so you can save by turning it off. If you are hesitant to try to relight it, you can ask your heating contractor to light it at the time of your annual service before the heating season.

Q. What is a "90 plus" furnace?

A. The term "90 plus" refers to the AFUE or percent efficiency. These high-efficiency furnaces are also referred to as "condensing" furnaces, as they extract so much heat from the exhaust gases that the moisture in the exhaust condenses, releasing additional useable heat. While these units cost more than a conventional furnace, in cold climates or homes with relatively high heating requirements, their lower operating costs can make them a good investment over the lifetime of the system.

Q. I currently use propane or LP gas for heating and water heating, but have natural gas available - should I consider switching?

A. Definitely. Natural gas is both less expensive and more convenient, and the modifications needed to your furnace and water heater are relatively minor.

Q. With a gas furnace (or water heater), what does the color of the flame indicate?

A. If the system is operating properly, the flame should have a bluish color. A yellow flame indicates a need for adjustment and should be checked by a qualified service person as soon as possible.

Q. What is the most efficient type of gas furnace?

A. There are several types of high-efficiency gas furnaces available. A condensing or "90 plus" furnace is typically rated at 89-93% AFUE, as compared with 78-80% for a new conventional-type furnace. Pulse furnaces, which work much differently, can have AFUE ratings as high as 97%.

Q. What is the best replacement option for an older gas "floor furnace"?

A. It depends on a number of factors. If you want to add central air conditioning you will need to add a duct system, which can be expensive. If you do add ducts, a new gas forced-air furnace would be good options. If you can't or don't want to add a duct system, consider natural gas space or room heaters, which will give you more flexibility and better temperature control.

Q. Should I install carbon monoxide detectors in my home?

A. Carbon monoxide detectors are recommended whenever a fossil-fuel heating system or water heater is present. In most cases, the danger of a heating system or water heater producing carbon monoxide is minimal, but under certain conditions any combustion process can produce carbon monoxide. Since carbon monoxide is colorless and odorless, it can go unnoticed unless a detector is present.

Q. When I first turn on my furnace at the beginning of the heating season, I notice a slight odor, as if something is burning - is this carbon monoxide?

A. No - carbon monoxide is odorless. If the smell lasts only a short while, it is most likely some dust or dirt being burned off of the heat exchange surfaces, and is harmless. If the smell persists, have a qualified contractor check your system.

Air Conditioning

Q. What is the most efficient thermostat setting for air conditioning?

A. The best setting is the highest temperature at which you are comfortable. The cost of operating your air conditioner increases significantly with each degree the thermostat is lowered. Most people can be comfortable at settings between 75 - 78°F. Using fans to increase air circulation can enhance comfort (moving air feels cooler) and allow a slightly higher thermostat setting.

Q. What does the term "tons" mean in the context of air conditioning?

A. A ton is a measure of the size or cooling capacity of an air conditioner. One ton is equivalent to removing 12,000 BTUs of heat per hour. For example, a three ton air conditioner can remove 36,000 BTUs per hour.

Q. When I replace my central air conditioner, would it be more efficient to get a larger unit? Will it make the house more comfortable?

A. It is best to get a properly sized unit. Although a larger unit may run for shorter periods of time, it will use more electricity due to its larger size. It may also fail to adequately dehumidify the home. A properly sized unit will control both temperature and humidity, making the home more comfortable.

Q. What does the "EER" or "SEER" rating on an air conditioner mean?

A. Both EER (Energy Efficiency Ratio) and SEER (Seasonal Energy Efficiency Ratio) are indicators of how efficient the unit is. The higher the number, the more efficient the unit and the lower the operating cost. SEER is used with central air conditioners, while EER is used with room air conditioners. For new central systems, SEERs of 15 or higher are generally considered high-efficiency units. For room units, EERs of 11 or higher are considered high-efficiency.

Q. What is the recommended SEER rating for a central air conditioner?

A. The current minimum requirement is 13 SEER. This is significantly more efficient than older units. Ratings of 13 to 15 are common, and units with SEERs as high as 20 are available. The more you use your central air conditioning, the more you will benefit from higher SEER ratings, and the more likely that the additional cost will be offset by energy savings.

Q. I have one room in my home that is always too hot in the summer - what can I do to make that room more comfortable?

A. If the room has a large area of exposed glass, keep curtains or blinds closed during daylight hours, particularly at times when the sun would shine directly in. You might also ask your air conditioning contractor to check whether you are getting enough air in that room - there may be a problem with your duct system.

Q. I have my air conditioning system checked every year, and it always seems to need "recharging" with refrigerant - is this normal?

A. Refrigerant does not shrink or disappear - a need for regular recharging indicates a refrigerant leak. The solution is to fix the leak, not to keep recharging the system.

Q. Will ceiling fans help cool my home in summer, and should I run them constantly, even when my air conditioning is running?

A. Ceiling fans can help make the home more comfortable, either alone or in combination with your air conditioner, by creating more air movement, which makes the air feel cooler. But remember that they do not actually cool the air, so there is no point in running them in unoccupied rooms or when no one is at home.

Q. Should I remove window air conditioners in the winter?

A. Window air conditioners should either be removed or sealed in winter to prevent cold air from entering the home and warm air escaping. Insulated covers are available which can be effective in reducing this air leakage if it is not feasible to remove the units. Sealing the inside and outside of the units with plastic sheeting can also help.

Q. What is a "whole house fan" and is it a good option for cooling my home?

A. A whole house fan is a large ventilating fan, typically mounted in a ceiling between the living space and attic. The fan draws air out of the living space and exhausts it to the attic, and then out through the attic vents. For the most effective ventilation, a window or windows in the lower part of the house should be partially opened, to bring cooler air into the home. These fans can be a good alternative to air conditioning in milder weather, but they do nothing to reduce indoor humidity. Because they draw indoor air out of the home, they should not be used at the same time as a central air conditioner.

Q. What is a "ductless" central air conditioner?

A. A ductless central air conditioner or "mini-split" system is a new type of central air conditioner with multiple indoor cooling units connected by refrigerant lines to a single outdoor condensing unit. Instead of using ductwork to distribute cooled air from a single indoor unit (like a traditional "split system"), this type of system has a separate indoor unit for each room or section of the home. This type of system is ideal for older homes with no ducts or for additions where adding ductwork is not feasible.

Water Heating

Q. How important is it to insulate my water heater?

A. It depends mainly on the location and age of the water heater. If the water heater is in an unheated area, more heat will be lost from the tank, making additional insulation more important. Newer water heaters have more built-in insulation than older ones, so you will save less by adding additional insulation. In most cases, you can save enough to offset the cost of the insulation, so unless your water heater has a label or sticker telling you not to add insulation, it is usually a good idea. Don't forget to insulate any exposed hot water pipes as well. Insulation blankets are NOT recommended on oil-fired water heaters.

Q. What is the best temperature setting for my water heater?

A. The lower the temperature setting, the lower your water heating costs will be. In most cases, 120° should be sufficient. If you have a large family and a relatively small water heater, you may need to set it somewhat higher, but no higher than 140°.

Q. How do I change the temperature setting on my water heater?

A. With a gas water heater, the thermostat control is a simple dial on the outside near the bottom. With an electric water heater, the thermostat controls are behind the access panels on the side of the water heater (there are usually two - one for each heating element). Be sure to turn off the power to the water heater before removing the access panels.

Q. What size water heater should I have?

A. It depends on family size and lifestyle, but for the average family of four, a 40 gallon tank is usually sufficient.

Q. Aside from adjusting the temperature, are there other easy ways I can save on water heating?

A. The simplest way to save is to use less hot water. Use low flow showerheads, wash clothes in cold or warm water instead of hot, and only run full loads in your clothes washer and dishwasher.

Q. What is an "instantaneous" or "on demand" water heater?

A. An instantaneous or on-demand water heater is a small water heating unit with no storage tank (and therefore less heat loss when no hot water is being used). Instead of keeping a tank full of water hot, they heat the water only when it is being used. There are two types - small "point of use" units that are well-suited for intermittent use areas and central units capable of serving the entire home. Both gas and electric models are available.

Q. What is the purpose of the pressure relief valve on a water heater?

A. The pressure relief valve is an important safety feature. It prevents a potentially dangerous pressure buildup in the water heater in the event that the thermostat malfunctions and fails to turn off the elements or burners. These valves should never be wired shut or otherwise tampered with.

Q. Should I drain my water heater, and if so, how often?

A. Some experts recommend draining water heaters once a year to remove sediment that can collect at the bottom of the tank and reduce the water heater's efficiency. If you decide to drain your water heater, be sure to shut off the power or gas supply, as well as the incoming water to the tank, and let the water cool down before draining it. Attach a hose to the drain and run it outside - do not attempt to drain the tank a small amount at a time, as sediment at the bottom of the tank may clog the drain valve, making it impossible to close until the tank has been fully drained and flushed. Once the tank is empty, turn the water supply back on and flush the tank until the water runs clear. Then refill the tank completely before turning the power or gas back on.

Q. Will a timer on my electric water heater help reduce my bills?

A. If you are on a "time of use" electric rate, and you set the timer so the water heater only operates during "off peak" hours, you should save money. You can do the same thing with an "on/off" switch, but the timer will do it automatically and never forget. If you are on a flat rate, the timer can still help some by minimizing heat loss through the tank, but may not save enough to pay for itself.

Q. Should I shut off my water heater if I plan to be away from home?

A. If you go away for more than a day or two, it is a good idea to turn off the water heater. If the water heater is electric, you can shut off the circuit breaker. With a gas water heater, you can simply turn the thermostat all the way down or to the "Vacation" setting if the water heater has one (this shuts off everything but the pilot light).

Q. I've heard that there is a system that uses a water heater to provide space heating - how does this work?

A. This type of system, called an integrated heating and water heating system, circulates hot water from the water heater through a coil of piping, and a fan blows air across the heated pipes and circulates the air through ducts. This type of system is most appropriate for apartments, condominiums or small homes, where the heating demand is minimal.

Q. How does a heat pump water heater work?

A. A heat pump water heater works much like a space heating heat pump - it absorbs heat from the surrounding air and uses it to heat water in the tank. Because it absorbs heat from the surrounding air, it should be located in a basement or other unheated area. During the summer, it can also help cool and dehumidify the basement.

Major Appliances

Q. I have a separate chest freezer - is this costing me a lot to run, and how can I cut the cost?

A. Refrigerators and freezers can be among the largest energy consumers in the home, especially older models. A separate freezer makes economic sense when you can buy large quantities of food and freeze it. If the freezer is empty or nearly empty, try to use the freezer compartment in your refrigerator and turn off the extra freezer.

Q. Are there any simple, inexpensive things I can do to save energy with my refrigerator?

A. Yes. First of all, keep the door closed. Make sure the door gasket fits snugly to keep the cold air inside, clean the coils (located either on the bottom or the back) regularly, and avoid overfilling the refrigerator - there needs to be enough room for the cold air to circulate.

Q. Is it a good idea to vent my clothes dryer inside to capture the extra heat in the winter?

A. Definitely not, unless you live in a very dry climate. The heated air blown out the vent also contains all of the moisture that has been removed from the clothes. This moisture can cause problems ranging from excessive condensation on windows to long-term structural damage.

Q. What is the purpose of the black and yellow "EnergyGuide" labels on appliances, and what do they tell me?

A. These labels allow you to compare energy costs of comparable appliances. Most will show a comparison of the least efficient model, the most efficient one, and where that particular appliance falls on the scale. They may also have a table that allows you to estimate your annual energy cost based on different electric or gas rates. . As with mileage ratings on automobiles, your actual cost may vary depending on usage.

Q. Can I save energy by using a microwave or toaster oven for cooking and defrosting frozen food?

A. Yes. Microwaves are excellent for defrosting and reheating cooked food, and use much less electricity than an electric range or oven. Toaster ovens also use less and are good for heating or cooking small quantities of food.

Q. Are there any simple ways I can save energy and money with my dishwasher?

A. Run full loads whenever possible (this also saves water), and use the "air dry" setting or open the door after the cycle is completed, instead of using the "heated dry" cycle.

Q. How can I save energy and money on washing and drying clothes?

A. Always use the lowest appropriate temperature settings (for both washers and dryers). If your washer has a water level setting, adjust the level to the load being washed. Avoid over drying clothes, and always try to run full loads, in both the washer and dryer. Weather permitting, try using a "solar clothes dryer" (clothesline).

Insulation and Weatherization

Q. What does the term "R-value" mean?

A. R-value is a measure of how well a material resists the passage of heat. The higher the R-value the more effective insulation is in keeping the home warm in winter and cool in summer. Insulation should always be judged by R-value rather than inches, as different insulation materials have different R-values per inch of thickness.

Q. How much insulation should I have in my attic?

A. Depending on your climate, attics should be insulated to between R-30 and R- 48. Your local utility should be able to tell you the recommended R-value for your location.

Q. If I install more insulation in my attic, what type should I use?

A. For do-it-yourself installations, most homeowners find it easiest to use batt insulation. Always use unfaced batts, as the paper or foil facing is a vapor retarder that can trap water vapor in the original insulation, causing moisture problems. If the existing insulation is level with the tops of the attic floor joists, install the new insulation perpendicular to the joists to reduce heat loss through the joists. Loose fiberglass or cellulose can also be used, by pouring it and leveling it with a board or other implement.

Q. If I install more insulation in my walls, what type should I use?

A. Exterior walls in new homes should be insulated to R-13 or higher, depending on climate. In existing homes, loose fill insulation can be blown into uninsulated walls. This can be expensive but in colder climates it can save enough energy to pay for itself over time. Have a qualified contractor check the walls and determine the feasibility of blowing in insulation.

Q. How much insulation should I have under my floor?

A. Floors over unheated crawlspaces or basements should be insulated to R-19, while floors over open air (such as overhangs) should be insulated to R-30 if possible. If your home has a basement containing your heating system or other sources of heat, you should insulate the basement walls to R-11 or R-13, rather than insulating the floor above.

Q. My home is built on a slab - is there a way to insulate my floors?

A. With slab construction, there is no practical way to insulate under the floor. In cold climates, new homes typically have the perimeter of the slab insulated to several feet below ground level. This can also be done in an existing home, but the cost and difficulty of trenching around the perimeter usually makes it impractical. In warmer climates, slab perimeter insulation is not considered cost-effective, and in locations where termites are a concern, it is not recommended as the insulation can provide a path for termites to enter the structure.

Q. Is it better to insulate the attic floor, the roof, or both?

A. Unless you are finishing the attic for living space, you should insulate the attic floor to contain the heat within the living space.

Q. Is it a good idea to add additional insulation to my walls, and how is this done?

A. If your walls currently have no insulation, insulation can be blown into the cavities through holes drilled through the exterior of the home. This should only be done by a reputable, qualified contractor. If there is already some insulation in the walls, you should not attempt to add any more.

Q. Can I compress 6" R-19 batts to fit into a 2"x 4" cavity, and will it be more effective than 3 1/2" batts?

A. While insulation batts are easily compressed, the R-value will be significantly reduced - it is best to use the correct thickness and not compress the insulation. You should also avoid storing heavy materials on top of attic insulation for the same reason.

Q. I've always heard that "heat rises". Why do I need to insulate my floors?

A. Actually, it is heated air that rises. Heat moves from warm to cold. If your home is built over a crawlspace or unheated basement, you can lose a lot of heat downward through the floors. Insulation will help reduce that loss and also make your floors feel warmer in the winter.

Q. If the walls and ceiling of my home are well insulated, do I really need to insulate my basement?

A. The importance of basement insulation depends on whether the basement is heated. If you heat your basement, or if your furnace or other sources of heat are in the basement, you should insulate the basement walls to contain the heat. If not, you should insulate the basement ceiling to reduce heat loss from the living space to the basement and keep your floors warmer.

Q. What is a "vapor retarder" and how important is it?

A. A vapor retarder is a material that resists the movement of water vapor. A properly installed vapor retarder can minimize the chance of water vapor condensing inside your wall insulation, which not only reduces the insulation's effectiveness but can also cause damage to your home. The vapor retarder should be installed facing the "warm in winter" side.

Q. I've heard that you can make a home "too tight" - should I be concerned about this?

A. It is difficult to build a home that is too tight, unless extraordinary measures are taken to eliminate air leakage. In homes that are built to be extremely energy efficient, an air-to-air heat exchanger can provide a supply of fresh air that is "pre-heated" by outgoing exhaust air. In an existing home, basic air sealing measures like caulking and weather-stripping are unlikely to make the home too tight for acceptable indoor air quality.

Q. What is the best type of insulation to use in my attic?

A. Either loose fill (typically fiberglass or cellulose) or batt insulation (usually fiberglass) will work well. Batts are easier to install yourself, while many contractors find loose fill easier and less expensive to install.

Q. Is it better to caulk my windows and doors on the inside or the outside?

A. Any large gaps on the outside should be weatherproofed to keep rain out, but the inside is generally the best place to caulk to keep the heated air inside, along with any water vapor that could condense in a cold wall cavity. Most modern caulking materials work well on either the inside or outside.

Q. How much ventilation should I have in my attic?

A. In most cases, you should have one square foot of net free vent area for each 150 square feet of attic floor area. Net free area is the actual area that air can flow through. With screens and louvers, you can assume that is roughly half the gross area. If you have a properly installed ceiling vapor retarder (which is unusual), you can reduce the vent area to one square foot per 300 square feet of attic floor area.

Q. How much ventilation should I have in my crawlspace, and should the vents be closed in the winter?

A. If the crawlspace has a dirt or gravel floor, you should have one square foot of vent area for each 150 square feet of crawlspace area, unless you have a waterproof ground cover, in which case one square foot for each 1500 square feet is recommended. Vents should not be closed in winter. If the floor over the crawlspace is uninsulated, you should have it insulated to reduce heat loss through your floors.

Q. What is the best way to ventilate a cathedral ceiling?

A. Cathedral ceilings should have continuous soffit vents and a ridge vent to allow air circulation between the insulation and the underside of the roof. Insulation should be installed with at least 1 inch of clearance from the underside of the roof. There are plastic baffles available that can be used to maintain this air space. A continuous vapor retarder is also recommended to minimize migration of water vapor into the insulation.

Q. Can I insulate over recessed lighting fixtures?

A. Only if the fixtures are designed to be covered with insulation (these fixtures are referred to as "IC Rated"). Otherwise you should maintain three inches of clearance around the fixtures and leave the top of the fixture uncovered to avoid potentially hazardous heat buildup within the fixture.

Q. What is a "thermopane" window, and how does it work?

A. A "thermopane" or double-paned window has two panes of glass, separated by a trapped air space (like a Thermos bottle). The trapped air acts as an insulator, reducing heat loss through the glass.

Q. My home has single-paned windows - would it be better to replace them with double-paned windows or to add storm windows?

A. Both double-paned windows and storm windows reduce heat loss by creating an insulating air space between the panes of glass. If your existing windows are in good shape, storm windows will usually be more cost-effective. If your existing windows are damaged or if you are replacing them for aesthetic reasons, you should install good quality double-paned windows. Selecting a window with performance U-Factors and Solar Heat Gain Coefficients (SHGC) of .4 or less will ensure the best results in summer and winter.

Q. Why does condensation form on the inside of my windows in winter, and how can I minimize the amount of moisture?

A. Condensation will occur whenever warm air hits a cold surface, because warm air can hold more water vapor than cold air. If you have single-paned windows, adding storm windows will keep the inner pane of glass warmer and reduce the amount of condensation. Monitoring your indoor humidity and keeping it in the range of 40 - 50% will also help.

Q. What are "Low-E" windows?

A. "Low-E" or "low emissivity" windows incorporate a microscopically thin layer of a metal oxide that reduces the amount of heat transferred through the glass. Low-E glass is sometimes combined with an inert gas filling between the two panes of glass (instead of air) to increase the insulating value. Selecting a window with performance U-Factors and Solar Heat Gain Coefficients (SHGC) of .4 or less will ensure the best results in summer and winter.

Q. I'm considering having vinyl siding installed on my home. Will this reduce my heating and cooling costs?

A. Vinyl siding is typically installed over a thin layer of foam insulation material. Although this material has some insulating value, it is minimal. You should be skeptical of any claims of substantial energy savings. The main benefits of vinyl siding are enhanced appearance, reduced maintenance and potentially increased resale value.


Q. Is it a good idea to turn off lights when leaving a room? Don't they use more energy when they are first turned back on?

A. You should turn them off. Incandescent or fluorescent lamps do not use any additional energy at start-up.

Q. Will compact fluorescents provide the same amount and quality of light as regular (incandescent) light bulbs?

A. As long as you use the correct size or wattage, you will get the same amount of light, and today's compact fluorescents have a much better quality of light and color rendition than old fluorescents - you really should not notice a difference.

Q. Can compact fluorescents be used in all types of fixtures?

A. There are a wide variety of compact fluorescents available that should fit most fixtures.

Q. Do the "energy saver" or "energy miser" incandescent bulbs save as much as compact fluorescents?

A. No, but they do use less than standard incandescents. They also last longer than standard incandescents, but nowhere near as long as compact fluorescents.

Q. What are LED lights, and are they energy-efficient?

A. LEDs or "light emitting diodes" are small solid-state light bulbs that are very energy-efficient. They use about one-third the energy of a compact fluorescent and can last up to ten times as long. In the past, LEDs were used mainly in electronics and instrument panels, but now there are versions available that will fit most standard residential fixtures.

Q. Does outdoor lighting use a lot of electricity, and how can I save while still protecting my home and property?

A. Electric use will depend on the wattage of the lights and hours of operation. Since outdoor lights are typically higher in wattage than indoor lights, the cost can be significant, particularly if a large number of high-wattage lights are used. You can save by limiting the hours of operation with timers, photocells or motion detectors.


Q. I've heard that waterbeds use a lot of electricity - is that true, and if so, how can I reduce the cost?

A. A typical waterbed heater will cost an average of about $15-$20 per month, depending on your electric rate. The best way to save energy and money is to keep the bed covered, keeping the heat in.

Q. Does an electric blanket use much electricity?

A. Very little (about $2.50/month), and it is much less expensive than keeping the whole house warm while you sleep.

Q. I often need to use a dehumidifier to control excess moisture in my basement. Is this costing me much, and if so how can I reduce the cost?

A. A dehumidifier running 12 hours a day will cost about $25-$35 per month, depending on your electric rate. Use dehumidifiers only as needed. In mild weather, try opening windows and using either natural air circulation or fans to dry up any excess humidity.

Q. Does a hot tub cost much to operate in terms of energy costs, and how can I reduce the cost?

A. The heater can use quite a bit of energy, depending on the size and whether it's electric or gas. An electric heater rated at 6 kW and used for 40 hours per month will cost about $25-$35 per month depending on your electric rate. The best way to reduce the cost is with an insulated cover that keeps the heat in and reduces the amount of time the heater needs to run.

Q. How much does my swimming pool filter pump cost me to run, and how can I cut the cost?

A. A one horsepower pump, used for 12 hours a day, will cost about $25-$35 a month depending on your electric rate. If you are on a "day/night" rate, you can save by running the filter pump only at night. Otherwise, limit the hours of operation to only what is needed to maintain water quality six to eight hours a day is usually sufficient.

Q. Can I save by unplugging appliances that are not in use?

A. If the appliance has an "on/off" switch, turning it off has the same effect as unplugging it. Extra refrigerators or freezers should be unplugged when not in use.

Q. What is "standby power" and how does it affect my electric bill?

A. The term "standby power" refers to power drawn by televisions, computers and other electronic devices when they are turned off or in standby mode. It is this standby power that keeps devices like televisions "warmed up" so they come on immediately when switched on. The U.S. Department of Energy estimates that the average U.S. home spends $100 a year to power devices that are off or in "standby" mode. You can reduce this standby loss by purchasing appliances and electronics labeled with the ENERGY STAR logo. These appliances must meet strict standards for reduced standby power consumption.

Q. I'm considering purchasing a new television. Which type is more efficient - plasma or LCD?

A. LCD or "Liquid Crystal Display" televisions are much more efficient than the plasma type. According to the American Council for an Energy Efficient Economy (ACEEE), the average LCD television uses less than 20% of the energy used by a plasma television.

Q. I'm planning on making several major energy improvements to my home, including adding insulation, installing storm windows and replacing my heating and cooling system. Does it make any difference which I do first?

A. As a general rule, you should try to make any improvements to the efficiency of the structure before replacing the heating and cooling equipment. The additional insulation and storm windows should reduce the amount of heating and cooling needed, which might allow you to install a somewhat smaller system than you currently have. A system that is properly sized to match the home's heating and cooling requirements will provide better comfort and efficiency, and any savings from down-sizing the system could help pay for the insulation and windows.

Q. What should I consider when hiring a contractor to make energy improvements to my home?

A. There is no foolproof method to guarantee a good job at a fair price, but there are some basic guidelines you should follow: always get a minimum of three estimates, ask for references (and check them), check with the Better Business Bureau or any consumer agencies in your area, and get everything in writing including a firm price, a start date and a completion date.