There are many features about a home that make a difference in the amount of energy needed for heating, cooling and lighting. Thus, these features can have a major impact on the amount of money you devote to maintaining the winter and summer comfort of occupants. This checklist will help you evaluate the energy-saving potential of various housing features.
Housing features to consider include: Site; House Design; Construction and Insulation; Heating and Cooling System; Color and Lighting.
- House is located on south or southwest slope of hill (sun hits at angle so greatest solar heat is received through south windows in winter).
- House is protected from winter wind by a hill or placement of garage/carport (air infiltration and heat loss are reduced when wind velocity is lower)
- House is built into a hillside or partially into the ground (the relatively constant year-round ground temperature reduces winter heat loss through below-grade walls and provides a cooling effect during summer).
- The long axis of the house runs east and west (allows more windows on the south to take advantage of winter sun, and south windows can be protected from summer sun by awnings, roof overhang, trees).
- Large deciduous shade trees are planted on south and west side of house (to provide summer shade during the hottest part of the day, but allow winter sun to heat house)
- Low evergreen trees and shrubs or a slatted fence are placed on side of house exposed to winter winds (to provide a wind break and reduce air infiltration,; avoid high evergreens on southeast, south and southwest as they block winter sun from house).
- Main roof ridge runs east and west (for better summer cooling and to provide a more desirable location for a solar heat collector in the future).
- Shape of house is a slight rectangle (long rectangles L-shapes H-shapes T-shapes and U-shapes provide more outside wall surface for heatloss).
- Entry halls for front and back doors can be closed off to form "vestibules" (thus reducing flow of cold air to inside and warm air to outside).
- Main living area, where the living room, family room, dining room and kitchen are located, has as few partitions as possible (for best heat distribution).
- Bedroom wing can be closed off (so heating and air- conditioning can be reduced when not needed during the day).
- South windows have an overhang or awning deciduous trees or vines (to shade from summer sun but allow winter sun into the house).
- East and especially west windows are kept to a minimum and/or provided with shade trees and tall shrubs, fences, awnings, tinted glass or other shading devices (to keep out early morning and late afternoon sun in the summer).
- Amount of window area is no more than 10 to 15 percent of floor area (there is more heat loss through glass, even double or triple glazing, than through an insulated wall). Note: Before you decide to eliminate certain openings, keep in mind that local building codes may require that certain rooms of the house have windows or doors to the outside. This is for safety's sake, especially fire safety. Check with the building inspector in your local area or county to be certain of requirements.
- Operable windows are placed so that cooling air can travel through the house in summer and escape at a high point of interior space (example: an operable window in an upstairs hallway will draw off warm air from the inside).
- Attic ventilators are placed so air is drawn from cooler, shady parts of house (under eaves for inlet of cool air) and exhausted as high as possible (along ridge of roof or at attic gable ends). Vents allow the escape of unwanted moisture from attic in winter and lessen attic heat build-up in summer (be sure ventilation is adequate; at least one square foot of eave inlet and one square foot of gable outlet for EACH 150 feet of ceiling area is recommended. Periodically check vents, especially eave vents, to see they are not obstructed by insulation or other building materials.)
- Chimney for fireplace is placed on an inside rather than an outside wall (so heat is lost to inside of house).
- Fireplace is designed to heat the room (such as a circulating type with a glass fire screen door to prevent heat from the room being lost up the chimney) and has an outside air intake for combustion of wood to prevent furnace heated air from being used for combustion (newer fireplace systems can be designed so duct-work connected to the system provides outside air for combustion; check with fireplace dealers in your area).
- Plumbing fixtures are located close to water heater(s) (to reduce heat loss from water as it moves from tank to point of use).
- Water heater is located in a heated space (even a well-insulated heater loses more heat when placed in an unheated area).
- Stair wells to second floor or basement have tightly sealed doors either at top or bottom of the stairs (to prevent "chimney" effect and loss of heat to upper area).
- Multi-family housing has "extra" energy saving potential In this type of housing, each dwelling shares one or more walls with other dwelling units (in townhouses, duplexes, or apartments in mid- or high-rise buildings, less wall space in each unit is exposed to the outside, thus greatly reducing the amount of heat loss from each unit through its walls, or ceiling and floor in some cases).
Construction and Insulation
- Insulated glass or storm windows used to reduce heat loss (storm windows and double-pane insulated glass will reduce heat loss by approximately 50 to 51 percent, while triple-pane windows will reduce heat loss by approximately 68 percent).
- Storm doors used on all exterior doors (storm doors will reduce heat loss through exterior doors by approximately 35 to 40 percent).
- Weatherstripping is installed around jambs of all doors and operable windows (heat losses due to infiltration can increase heating costs by sizeable amounts).
- Caulking around all door and window frames is in good condition to reduce infiltration heat loss (caulking normally dries out with time and needs replacing).
- Heating ducts/runs are wrapped with insulation except where they pass through heated rooms (metal runs in unheated crawl spaces, basements and attics lose heat to these cold areas). Note: If possible, the system should be designed so heat runs do not pass through unheated areas.
- Hot water pipes are wrapped with insulation except where they pass through heated areas (metal or plastic pipes in unheated crawl spaces, basements and attics lose heat to these cold areas Note: If possible, the water supply system should be designed so pipes do not pass through unheated areas.
- Attic and gable areas are adequately ventilated (see point above in design features section concerning attic ventilation requirements).
- Sill sealer/filler has been placed around top of foundation wall below sill plate (to reduce infiltration into basement area).
Heating and Cooling System
- Thermostat is located on an inside room partition (thermostats on exterior walls, near windows, near heat-generating appliances, in drafts or in sunlight may not react to actual room temperature, hence will not keep room temperature within limits desired).
- Heating controls are designed to allow for zoned heating (permits heating of lightly used areas only as needed). Note: In some homes, heating runs or registers may be designed with dampers or valves which allow you to stop the flow of heat into seldom used rooms (these can be added by heating and cooling professionals); while in other homes, zoned heating may be achieved by the use of two thermostats, one controlling the bedroom area and one controlling the living area (a more expensive alternative).
- Mechanical ventilators/fans in kitchen, bath and laundry fit tightly, are weatherstripped and have positive closure shutters (ventilators without shutters allow excessive backdrafts of cold air into home).
- Furnaces are located as centrally as possible in house (to reduce lengths of both hot and cold runs to shortest possible distance).
- Furnace design and location permit easy access to air filters (clogged filters reduce efficiency).
- Humidity level of home is kept at 30 to 40 percent during the heating season (warm air feels warmer and more comfortable when humidity is present in the air; humidity can reduce static electricity problems as well). Note: Portable humidifiers located centrally in home will add humidity, or power humidifiers connected to forced air furnaces will add humidity.
Color and Lighting
- Outside walls and roof are a light color if summer heat is a greater problem than winter cold, such as in uninsulated summer cabins (light colors reflect the sun's heat while dark colors absorb it).
- Interior wall and ceiling colors are light tints or white (so both daylight and artificial light are reflected more than absorbed).
- Floor covering is medium to light in color (so light reflectance will save on amount of artificial light needed).
- Overhead lights in living areas and bedrooms provide good over-all light for less total wattage than several lamps; lamps can then be used for task lighting of areas as needed (simple fluorescent enclosed fixtures, flush with the ceiling, will provide excellent light with little energy use; incandescent fixtures may be preferred by some).
- All light fixtures are located so they can be easily cleaned (dust on bulbs, tubes and fixtures reduces illumination).
For more information on energy conservation in your home, contact your local Extension Home Economist and ask for copies of a series of"Energy Fact Sheets" and other energy related materials made available by the Michigan State University Cooperative Extension Service.
This information comes from Michigan State University Extension bulletin E1384, A Checklist for Energy-Saving Homes.
Source: MSU Extension