5 Surprising Materials Used to Build Green Homes

The housing bust that brought us into the recession may very well bring us out of it, according to economists encouraged by reports that housing sales have risen for two consecutive months. And a few of those sales have been for homes made with recycled tires, shipping containers, or straw. Alternative building materials like these can save builders money,cut back on the use of unhealthy construction materials , and in some cases, cost much less than that cute little Cape Cod one cul-de-sac over. Even if you're not contemplating a housing start anytime soon, these five clever ideas make good motivation to make smaller changes for a greener household.

#1: Shipping containers. Our insatiable demand for consumer goods has indirectly created a market for alternative housing. Shipping containers land on American shores full of stuff every day, and since the U.S. has few exports, many containers just sit empty in shipyards. Shipping companies could pay $900 or more to send them back, empty, or they could sell them to you for up to $6,000 each to use as trendy, avant-garde building materials. Architecturally, they're perfect for shelter—fireproof, waterproof, already insulated (if you buy the refrigerated kind), and sturdy enough to stack 12 on top of each other without collapsing. As an added design bonus, most shipping containers have hardwood flooring that simply needs sanding and a coat of finish to shine like new again. The cost for such a home varies widely, but Quick Build LLC, an architecture firm based in New Jersey (home to the largest shipyard on the Eastern seaboard, in Elizabeth), will build you a six-container home of roughly 2,000 square feet for $184,0000, excluding shipping and the cost of land.

The house above, designed by architect Peter DeMaria, was constructed from eight shipping containers. The wall was the door to an old airplane hangar.

Courtesy DeMaria Design

#2. Cob. Fairytale-like houses first seen in England and Wales are now taking root in the U.S., too. Similar to adobe, cob is made with a mixture of clay and sand, but also includes a high percentage of straw fibers, and the clay/sand/straw mixture can be applied wet with your bare hands. That mixture is what supports the entire house—dry cob is extremely strong—so you need virtually no construction know-how to create a cob structure. Some cobbers build their homes after taking weekend or weeklong workshops that teach how to build with cob in that short a period of time. The material has good thermal mass, releasing heat during the summer but retaining it during winter, and while it doesn't seem that it could stand up to rain, dry cob is just as moisture-resistant as brick. One operator of cob instructional workshops estimates that you could theoretically build a small cob cottage for $5,000 in materials.

Courtesy Gary Zuker

#3: Tires and trash. One man's trash…forms the walls of another man's Earthship. These quirky houses are made mostly from old tires stuffed with earth, but their concept's originator has taken to using everything from aluminum cans, glass bottles, and old appliance parts for roofs and interior walls. Earthships are situated so that portions of the home are covered by earth, which keeps the home at a constant temperature year-round. The south-facing wall of windows brings in light and warmth in the winter. According the Michael Reynolds, the architect behind the homes, the houses cost about the same amount, per square foot, as conventional homes, but you make up for that cost in your utility bills, which can run as little as $100 per year.

Courtesy Kirsten Jacobsen, Earthship Biotecture

#4: Straw bales. In many applications, straw bales are used for insulation in standard wood- or steel-frame houses, but stacked on top of each other and covered in plaster, they're actually strong enough to be load-bearing. It's the ultimate green building material since it grows everywhere and can be acquired locally, but you don't even need to grow the material; 200 million tons of waste straw are produced in the U.S. each year. Straw bale builders also estimate that they lower your utility bills by 75 percent, because of straw's insulating abilities and because the builders build tight leak-proof houses to prevent water from seeping into walls and rotting the straw.

#5: Legos. It had to happen sooner or later—the ubiquitous children's toy known for building model structures is being used to build a real-life house in the middle of an English vineyard, complete with a Lego toilet and Lego shower. James May, the host of the BBC 2 series "James May's Toy Stories," is currently building the house, and upon completion, which is expected this weekend, he has promised to live in it for the weekend. This house would probably be so leaky that trying to heat it would be pointless, but it just goes to show you that recycled building materials are everywhere. The series documenting the project aired in Spring 2010.