"Since 1950, the average size of new single-family houses in the United States has more than doubled, even as the average family size has steadily shrunk. More area (square footage) per family member is being used than ever before, and projections are that the trend will continue. As house size increases, so too do the environmental impacts associated with buildings and development: resource consumption increases, the land area affected by development grows, stormwater runoff increases as impermeable surface area increases, and energy use rises. In addition to carrying larger environmental burdens, larger houses cost more to build and operate. For single-family houses, "small is beautiful" in terms of environmental performance."
Thanks to Brenda Meyer