Building with a better brick
Let's start with a common building block in a lot of homes and backyards: the brick. Bricks are popular, but they're not environmentally friendly. They're typically fired in a huge oven for as long as four days at 2,000 degrees.

"You're burning either coal or natural gas, and it emits a pound of (carbon dioxide) for every brick," says Karen Righthand, director of marketing for CalStar Products, which makes an alternative brick from fly ash, the material that's left over from burning coal.

"Years ago, before clean-air laws, that ash would just fly out the smokestack and deposit all over," Righthand says. "Now it's collected, and we can use it."

The fly ash is mixed with sand, water and pigments. The mixture is molded and cured overnight in a low-heat, humid environment. "It literally takes a tenth of the energy to produce it that way," Righthand says.

CalStar opened its plant in Racine, Wis., in January 2010, and Righthand says the products are starting to catch on, particularly in the Midwest.

"Bricks and pavers are heavy, so they're not something you're going to see in all 50 states yet," she says. "People tend to use more local materials when they're really heavy like that."

What does recycled mean?
It's important to note that not all recycled building products are created equal. If something is made from a product that has been used before — glass bottles, blue jeans, rubber tires — it's post-consumer. Post-industrial materials, on the other hand, are made from factory waste and have never been in consumers' hands.

"(Post-industrial) is kind of a cleaner recycling, but it's never had a first use," says Alli Kingfisher, a building-materials and sustainability specialist with the Washington state Department of Ecology.

Post-industrial recycling is important, but post-consumer products have already served their intended purpose and are essentially getting a second life through recycling. "We're doing as much as we can to promote post-consumer recycling," Kingfisher says.

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She helped start a home tour to educate homeowners in her area about available recycled materials. "There are so many things you can get that do have recycled content in them," Kingfisher says. "It's just whether or not you are paying attention to that."

In most cases, it's not clear just by looking that something is made from recycled materials.

"It's just like not knowing if something is organic or fair trade unless you ask about it," says Kristi Neidhardt, a Maryland real-estate agent who specializes in "green" homes. "It's becoming more and more trendy, and people are starting to ask and look for it."

Looks can be deceiving
One example of a recycled product that certainly doesn't look it is carpet made from soda bottles. Mohawk Flooring makes a carpet called EverStrand, with as much as 100% of its fiber made from recycled content.

Bart Rich, a director of brand management at Mohawk, says the motivation behind the carpet wasn't to be green. Recycled bottles provide a superior form of polyester because they're made for food-grade products and must meet Food and Drug Administration requirements. "When you melt (them) down and put it back into a polymer, it makes a better performing carpet," he says. "It wasn't that big of a deal until green became such a huge factor."

The carpet is also stain-resistant and allergy-friendly.

So recycled products can provide benefits beyond saving the environment. That's true of Euroshield rubber roofing, which is made from used tires and comes with a lifetime warranty. It's also impact-resistant and relatively maintenance-free. Other recycled roofing materials, such as plastic or metal, can provide similar durability.

But some recycled materials are just plain good-looking. A company called Kirei recycles sorghum, wheat straw, hemp and wood into sleek-looking panels used for wall coverings, architectural millwork and cabinetry. Kirei was founded with the premise that "green should be beautiful."

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A countertop made from recycled glass can be colorful, unique — and sparkly.  One maker of recycled-glass countertops, Vetrazzo, builds its slabs with 85% glass; the rest is concrete. That's a lot of sparkle.

One goal of Kingfisher's home tours in Washington state is to show homeowners that recycled products have visual appeal, she says. "We're getting them exposed to being able to go in homes and look at concrete countertops with fly ash and recycled glass bits," she says. "If people can see things and touch them, they get excited about it and see they can be beautiful."