There are 132 million housing units in the U.S., of which about 95 million are single family homes. Most are built with the same materials—pine or fir wood frames, gypsum board walls, concrete or cinder block foundations and asphalt shingle roofs. They’re assembled with power tools and methods designed for speed—a new home can be built in just a few months, and close to a million are built every year.

Modern urban houses are the most visible and ubiquitous products of the industrial age, not just by their presence but in how they have transformed the land. They have a large impact on the environment, on the depletion of natural resources and on energy consumption.

Homes used to be simpler. Through most of human history houses were built with mass walls: stones, logs or masonry stacked on top of each other. Local materials were most often used, and few resources were consumed, outside of burning wood or peat for heating.

The Industrial Age transformed home construction. To the citizens of the newly formed United States, the country seemed to have a limitless supply of forestland stretching westward. From the early 1800s, steam-powered sawmills efficiently cut lumber that was transported across the country by river, canal, and train. Newly-invented power tools produced wood in standardized sizes, which led to the first light-frame construction that is common today, using 2x4 studs joined by nails. This new way of building was faster and required less skill than previous methods.

In 1908, Sears and Roebuck started selling pre-cut house kits starting at $360 (about $8,600 today). Other companies emerged that specialized in pre-fabricating doors, windows and other building materials. Gypsum board, or drywall, was introduced about this time, significantly lowering the cost of interior wall finishing.

In the years following WWII, the average American family could aspire to own a house and an automobile. The auto made it possible to live farther from city centers, giving access to land for home ownership. Acres of farmland, which had once been forest, now became suburban housing developments.

On average, Americans now live in the biggest houses on Earth. The average size of a new home, in square feet, has grown from 983 in 1950 to 2,701 in 2013. Households also consume more energy today, with increased use of electrical devices and greater use of air conditioning.

More than 80 percent of Americans — almost 250 million people — now live in urban or suburban areas. Over the course of two centuries, large parts of the American landscape have been transformed from forest to farm to suburbs.

U.S. Population over time in millions.

Average size of homes in square feet over time.

U.S. electricity per capita in million Btu over time.

New house construction averages about 2,700 square feet in indoor space today. The amount of material to build one varies significantly based on the plan, so the above numbers are very approximate, but it does take a lot of materials to build a single house. This also doesn’t include the amount of wasted material, and the energy and resources needed to manufacture and transport the materials, and the energy used in the construction itself.

Environmental Movement

Environmental concerns in the U.S. go back to George Perkins Marsh, who wrote ‘Man and Nature’ in 1864, in which he argued that deforestation could lead to ecological disaster. But in spite of his warnings, by the start of the 20th century most of the East Coast’s old growth forests were gone, and by now almost no original forest land remains in the U.S.

The first regulations to protect air and water quality were proposed in the 1940s and ‘50s. The first significant land protection law was the Wilderness Act in 1964. Since then, there have been a succession of laws aimed at protecting the environment.

Environmental concerns gained traction in the 1960s due to high profile events such as Cleveland’s Cuyahoga River fire, and in the 1970s thanks to sharply rising oil prices. The EPA–the Environmental Protection Agency–was established in 1970 with the task of regulating air and water quality.

U.S. Crude Oil Purchase Price (Dollars per Barrel)

Green Building

The green building concept grew out of environmental concerns about wasting natural resources and energy in home construction. Also known as sustainable building, it promotes construction that:

Although building codes in the U.S. are strict, they mostly address the structural safety and soundness of a building. Making it green is voluntary.

The history of green building is very recent:

The certification for home builders is now called the NGBS, or National Green Building Standard, which awards bronze, silver, gold and emerald levels based on the number of points earned in a questionnaire. The form can be seen here.

Demand

There is virtually no demand from home buyers for sustainable construction materials or features. Builders see no profit incentive, since buyers are primarily concerned with getting the most space and features in a new home, and in living in a desirable neighborhood. Green features are very far down the list for most buyers. As a result, building materials and practices have changed little since the inception of the green building movement.

The only impetus behind sustainable building practices is from government regulation, which has had varying success. The Energy Star program to make appliances more energy efficient has had a positive effect, for example. But most other steps that could be taken, such as replacing conventional materials with sustainable ones, or converting the energy grid to solar, are not being implemented.

As a result, there are virtually no completely sustainable houses being built today. Whether that changes in the future will depend on politics, public perception and the rate at which resources become scarcer.