In Portland, Ore., an analysis from the Earth Advantage Institute found that green-certified new homes sold, on average, for 8 percent more than non-certified green homes--and in one of the counties included in the study even more than 23 percent higher. Earth Advantage Institute analyzed sales data from May 2010 through April 2011 from the Portland Regional MLS.

The study found that the sales price was even higher for existing homes outfitted green -- an average of 30 percent more, and one county reporting a more than 61 percent premium on green-certified homes.

The green certifications on the homes were from Energy Star, LEED for Homes, Earth Advantage, or an Earth Advantage/Energy Star combination.

This is the fourth year in a row that the Earth Advantage Institute has conducted such a study and has found green-certified homes sell for higher prices than non-certified homes.

“There's certainly a premium there to be had,” says green builder Josh Wynne from Sarasota, Fla. “Clients are naturally skeptical of green building. If you're disingenuous or sell green as an upgrade like a granite counter,” it won't work.

But the hook, experts say, is to promote the upgrades by showing the energy savings that green homes can offer. (Learn more from NAR’s GREEN certification program.)

Source: “Green Homes Sell for More, Studies Show,” EcoHome (Aug. 1, 2011)