A Guide to Buying Eco-Friendly Homes

Five years ago, anyone who wanted to build an environmentally-friendly home could expect to pay a premium of 11% to 25%, depending on just how green they wanted to go. Now, they'd pay just 3% to 5%, says Jim Amorin, vice president for the Appraisal Institute, a professional trade organization. Those extra costs can easily be offset by the long-term savings on electric and other utility bills these homes offer. Just using an energy-efficient furnace or boiler could save you $570 annually, according to the Department of Energy.

Another selling point: While the average U.S. home lost 5.7% of its value in 2007, eco-friendly homes have held their value, even appreciating in price. Come sale time, a green property typically appraises for 10% to 15% higher than comparable conventional homes, depending on region and which upgrades were made, says Amorin.

All these factors have made buying an eco-friendly home much more attractive to prospective buyers. Green homes are expected to account for 10% of new home construction in 2010, up from 5% in 2005, according to McGraw-Hill Construction, a market researcher.

From the use of recycled materials in the flooring to the mere installation of a water-saving toilet, what qualifies as "green" will vary by consumer, neighborhood and home builder. "There are some builders who claim a property is a green home because they've increased the energy efficiency by 5%. That doesn't excite me," says Alex Pettitt, a green builder and host of Mainstream Green, a web TV show. Consumers can save that much on monthly utility bills just by switching to Energy Star appliances.

Here are four things you should do while shopping for an environmentally-friendly home: