Green Homes Selling Faster, for More

A recent analysis of the Northwest Multiple Listing Service (MLS) of King County, Washington demonstrated that third party certified energy efficient homes sell faster and have higher values.

For the past year the Northwest Multiple Listing Service has included information on a home’s green design features to its property listings database. The MLS listings also indicated whether the home was third party verified. The MLS is a critical tool used by real estate agents in showing homes to potential homebuyers and by appraisers in identifying comparables in developing the market appraisal for the home.

The Seattle based GreenWorks Realty completed an analysis of the market performance of homes that were certified as energy efficient green homes in the MLS. The analysis found that certified energy efficient homes in King County sell in up to 18% less time and for 28 – 37% higher value per square foot than non-certified homes. Single family certified homes sold in 18% less time and were valued at 37% more per square foot. New certified condominium units were valued at 28% more per square foot.

Below is a comparison of new construction certified green homes to non-certified homes sold in King County from September 2007 through May, 2008:

Non-Certified Number of Single-family Homes Sold
Median Sale Price
Median Square Footage
Number of Condominiums Sold
Median Sale Price
Median Square Footage

Additional data from the analysis is posted online at

GreenWorks Realty founder Ben Kaufman led the charge to introduce energy efficiency and green certification search categories in the market’s MLS. He commented, “The new data shows buyers are indeed going green and certified homes have more value. This is good news for our kids, our communities, our planet … for all of us. We also see green homes command a higher return on investment. This information encourages savvy remodelers and builders to make green a priority.”

Aaron Adelstein, Executive Director of Built Green of King and Snohomish Counties had the following comments on the study, “Until now, the idea that people are willing to pay more for environmentally-certified housing has mostly been based on surveys and expectation. Now we have the first hard data to back up what many of us have believed for a long time – green homes have greater value.”

Distributed by Healthier Dwelling: helping homeowners & realtors increase the value of their homes by doing 3rd Party Certification of Green/Sustainability/Energy efficiency. Contact: 415.717.5697