Patricia Skinner, Attaway, Denise | 5/3/2007 11:40:12 PM
Mobile homes have been steadily growing in popularity as a temporary and permanent primary residence for many Louisiana residents. Mobile homes can provide years of comfortable and convenient living, while giving you the most for the dollar you spend on electricity. Using the following energy conservation tips will help you to make the least of your electric bill.
The single largest user of energy in the mobile home in the Gulf Coast area is the air conditioning system. The peak energy use for the air conditioning occurs during the hot and humid months of June, July, August and September. The air conditioning system functions much like a refrigerator in that air removes heat and moisture from the interior of your home and replaces it with cool, dry, filtered air. Unnecessary heat and humidity from the outside can cause the system to work overtime, resulting in needlessly high utility bills. Properly installed and maintained equipment is a must if your air conditioning system is to operate efficiently.
Ductwork: It is extremely important that the return air duct is tightly sealed. Outside air can be pulled in from the slightest crack, placing an additional work load on the air conditioning unit. A simple, periodic check on the condition of the ductwork should become part of your routine maintenance around your mobile home.
Since most ductwork is usually located under the mobile home, skirting from the mobile home to ground level, or even a couple of inches below ground level, will usually help you get the most out of your air conditioning system in summer and the heating system in the winter. It will also help keep pets and other small animals from tearing out the duct system insulation, or the ductwork itself.
Weather stripping and caulking are relatively inexpensive and easy to apply and are very important in helping you keep your utility bill as low as possible. Using a caulking gun or putty knife, plug and seal all openings with a quality caulking compound after you have cleaned the area to insure proper adhesion of the compound. The best compounds remain elastic when dry and are available in colors to match exterior finishes.
Weather stripping comes in a variety of materials from foam strips to bronze strips. Check with a reputable hardware store to determine the best type for you in terms of cost, durability and ease of installation, (For more details on caulking and weather stripping, write for the Department of Natural Resources' free brochure Caulking and Weather Stripping or click "here" for the printable online version of the brochure).
Filters: The return air filters of your air conditioning and heating system should be changed or cleaned regularly. Dirty filters slow air movement and increase the system's running time. Permanent filters should be cleaned weekly, and the disposable ones should be replaced monthly. The savings in your electric bill will more than offset the small cost of filters.
Ventilation: Ventilation is another load on the air conditioning system that can be dealt with by the mobile homeowner. Removing moisture from Louisiana's humid atmosphere is a large part of your system's function. Cooking and bathing increase the humidity level inside any residence, but proper ventilation can decrease the strain on your air conditioning system and your pocketbook.
Range hoods and bathroom vents can remove considerable moisture from your living area and do it with considerably less effort and expense. Where ventilators can be placed on the roof, heat which is trapped in the space between the insulation and roof can be removed. This results in a cooler attic area and ceiling, which are very important to both comfort and lower electric utility bills.
A thermostat setting of 78-80° F is recommended during the summer. Since high humidity, such as we experience in Louisiana, helps your body hold heat, the use of a dehumidifier improves the comfort level and requires less energy than running the air conditioning system. Ceiling fans and oscillating fans also help control humidity by increasing air circulation to promote evaporation of excess moisture (humidity) of your skin.
In the winter, a thermostat setting of 65° F is recommended. Again, humidity affects your comfort level. A properly humidified room is as comfortable at 68° as a dry one at 72°. A humidifier or even a vaporizer can add all the moisture you need. To prevent deterioration, it is best to keep humidity levels between 30-35% average.
Siting and Shading
Much of the comfort you seek in your mobile home and the home's efficient use of energy are determined by its placement of siting. In southern latitudes, a mobile home should be positioned in an east-west direction so that the rays of the sun will not hit your home broadside. Also consider the location of trees when siting your mobile home.
Free standing trees provide an effective shading device that can affect not only the walls of your mobile home, but also its roof. Deciduous trees let the sun in during the winter and provide shade during the summer. Evergreen trees provide constant shade and this may be undesirable during winter when the sun's rays can be used to help warm your home.
As the number of trees increase, their effect on the house will change. A grove of trees will not only provide shade and wind protection, but modify outside air temperature through vaporative cooling. Experiments have shown a difference in shaded and unshaded outdoor wall surfaces of 8° F. Other research reports show that shade trees will reduce heat gains by 40 to 80% depending upon their placement and density.
Solar radiation (the sun) is probably the greatest source of heat gain in your mobile home. Since the sun contributes large amounts of heat, it is only logical to consider these points. Is your mobile home located in shade, or is it in the wide open space? If it is unshaded in the open and you cannot move it to a shaded area, then consider building a canopy over the mobile home to block the direct sunlight. If possible, position your mobile home in an east-west direction so that the rays of the sun will not hit your home broadside. Window and door awnings can be a great help. There are also protective (reflective) roof paints available on the market to reduce radiation.
Owners of flat-roofed mobile homes can add a pitched wooden gable roof above the original roof. Such a roof addition provides a barrier from the sun's direct rays and also offers an excellent opportunity to add loose fill insulation or fiber-glass batts to meet recommended energy savings standards.
Some mobile home owners prefer to build a large "patio" type cover over the mobile home and extend it over both sides. This provides extra protection for the roof and helps shade the sides of the home, while providing the roof for a porch or covered patio.
In hot, humid regions of Louisiana orient the active living zones of your mobile home 5° south-southwest, and if possible use trees or shrubs to cut northern winds.
No less important is air infiltration. Air can infiltrate through cracks around doors and windows. Check your doors. Is there a noticeable space between them and the door frames? If there is, add or replace the weather stripping and caulking. Make the same test at all your windows. Can you feel air? If you can, then you've just discovered another wasteful trouble spot. Other areas to check are around the moldings, joints, roof vents, and wheel housings.
Purchasing a Mobile Home
When you purchase a new mobile home, buy according to the Mobile Home Construction and Safety Standards issued by the U.S. Department of Housing and Urban Development (HUD), effective June 15,1976.
A mobile home built according to Subpart F of the HUD standards meets basic requirements for condensation control, air infiltration, thermal insulation (in the ceiling, walls, and floors), and has a label permanently affixed on an interior wall certifying, according to climatic conditions, the capability of heating and cooling equipment. A home insulated to HUD's performance standards is more comfortable in winter and summer and is more economical to operate than a home with less thermal protection.
After air conditioning and heating, hot water accounts for the next largest part of your utility bill. About 14% of your energy bill is for heating water for bathing, washing dishes and washing clothes.
If your mobile home is like most, the water heater is located in an outside compartment, barely separated from the weather by a lightweight vented door. This means the heater loses heat to the outside air. You cannot seal the vent in the door because it is necessary to provide outside air for combustion and safety, but you can insulate the water heater.
Install a water heater insulation jacket to keep the heat inside the tank. This requires less energy to keep the water hot. When you install the wrap, do not cover the control area -- and, if it's a gas heater, do not cover the top of the tank or block any air vents. This can be extremely dangerous.
Check the thermostat on your water heater. A low setting uses half the energy of a high setting. For a small household with limited hot water demands, a setting of 120° F is usually satisfactory. For the majority of all households, it is usually not necessary for the temperature setting to be any higher than 140° F.
Also check for any exposed water pipes. They should be insulated for two reasons: to protect them from freezing and to retard heat flow from the piping surfaces.
Drain some water from your water heater. Is their sediment in the water? If so drain the heater until the water runs clear. Sediment in the water heater acts as an insulator and makes the heater work harder to warm the water. Check for sediment once a month.
Dramatic increases to a window's R-value are possible through the use of drapes, shutters, and shades, especially the types designed to improve a window's insulating performance. But to be effective, they must be operated correctly. That means closing them at night and opening them selectively during the day to let winter sun in and keep summer sun out. In winter, north-facing windows are best kept covered. East-facing windows should be allowed to admit early morning heat and light. They should be covered in the afternoon. When the east windows are covered, it is time to expose the west-facing windows. Those on the south side can take advantage of the winter sun all day long.
During our hot, humid Louisiana summers, measures that reduce the amount of sunlight entering through windows are among the best in terms of saving on cooling costs. Outdoor shade that blocks impinging heat and light before it enters the home is best, but internal shade is also effective.
Applying common sense to windows has the potential to save mobile home dwellers substantial sums of energy and money.
Louisiana Department of Natural Resources, Technology Assessment Division, Energy Section, 625 N. 4th Street, Room 234, P.O. Box 44156, Baton Rouge, LA 70804-4156 Telephone: 504-342-1399