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57 Ways To Protect Your Home Environment (and Yourself)
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51. Design New Homes For Energy Efficiency

building orientation

When designing a new home, many basic decisions affect energy consumption. For instance, a square building has less wall area per square foot than does a rectangular building of the same size; therefore, a square building has less heat loss per square foot. Also, a larger building has less heat loss per square foot than a small structure.

Placing a rectangular house with the long axis east to west will mean less solar heat gain in the summer and more solar heat gain in the winter. Also, a properly designed roof overhang on the south wall will protect the wall from summer sun without blocking winter sun.

patio door

For a given area, windows and doors lose more heat than walls do. A double-glazed window can lose seven times as much heat as an insulated wall. A vestibule with an inner door reduces the flow of air in and out of the living area. This works especially well in homes with heavy traffic due to children and pets.
unshaded house

In the summer, the amount of unwanted solar heat gained through unshaded east and west windows is twice as great as through equal-sized south windows. Also, a wide porch serves as an outside living space and shades the walls and windows against solar heat gain.
caulk the joint between the sill and the foundation

Placing a compressible filler on the foundation before the sill plate is fastened will reduce air infiltration. On older houses, caulk the joint between the sill and the foundation.
light colored roof

A light-colored roof reflects more solar heat than a dark-colored roof. But this is not as important if the attic is properly insulated and ventilated. Also, install continuous vents in the roof overhang and on the roof ridge to remove solar heat and eliminate the need for power venting.
The floor of a room over a garage should have 6 to 9 inches of insulation and a vapor retarder.

The floor of a room over a garage should have 6 to 9 inches of insulation and a vapor retarder. In the crawl space, cover the entire soil surface with a polyethylene vapor retarder. This prevents moisture from evaporating in the crawl space and moving as a vapor into the house.

A chimney on an inside wall loses less heat to the outdoors and provides a better draft than a chimney on an outside wall.
Geothermal system

To cut your heating bill by 40 to 70 percent and your cooling costs by 30 to 40 percent, you might consider a geothermal closed-loop heat pump. This alternative heating and cooling system taps into underground temperatures, which stay at about 55 degrees F year-round.
Geothermal system

In this system, loops of pipe buried in the ground draw from an inexhaustible energy source—the sun’s energy that is stored within the earth as heat. In winter, the ground is a heat source. In summer, it is a heat sink; hot air is drawn from the house and pumped into the ground.

The geothermal system is also environmentally sound. It delivers over 3 units of energy for every unit of energy it consumes. However, because of considerable installation costs, it is ideally suited to someone who is building a new home or is replacing a home’s heating system.

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