Windows can be a major source of heat loss/gain. In 1990 alone, the energy used to offset unwanted heat losses and gains through windows in residential and commercial buildings cost the United States $20 billion.

he cost of heating and cooling some older manufactured homes, however, can be twice as much as site-built houses of comparable size and age.

Lighting accounts for around 20 percent of the electricity consumed in the United States. Turning lights and PCs off when they are not needed is a low-cost technique that saves money.