Passive solar house design Washington

Aug 17 2010

Seattle is notorious for being a wet, cold, dark environment in the winter. However, Seattle, and all of western Washington, still has  ample “insolation” for passive solar buildings. In fact, Seattle has better solar potential than northern Germany, where glassed-in porches have been part of housing for roughly a hundred years.
As opposed to solar electric systems that require sunshine to be effective, “solar thermal,” meaning space heating or water heating, doesn’t require bright sunlight…just light, which is transformed into heat when it passes through glass. There are straightforward  principles of passive solar house design in Washington: Identify the volume of the space to be heated, size appropriate south-facing glass, and then size the proper amount of thermal mass to store the accumulated heat overnight.
Anthony Stoppiello has been involved in passive solar house design in Washington since 1993, including major remodels of existing houses to enhance their solar potential. The Kess-Spackman home on the eastern shore of Willapa Bay is a good example of incorporating direct gain passive solar principles, excellent natural light…and disabled accessibility, including an elevator for one of the home owners.
A new house is easier to design and build, but still requires an experienced solar architect to evaluate the site and work with the client to develop their functional and aesthetic requirements.
Contact Anthony at 503-368-6141 for more information on passive solar homes and for on-site evaluations.

Anthony Stoppiello has been a pioneer in passive solar homes in Oregon and Washington for 30 years.

2 responses so far

  1. have an existing 800 sq.ft. 100 year farm house which is gutted. It’s south facing side is where I want to expand with @ a 500 sq.’ add.


  2. Roselie Rasmussen

    Hi Anthony,

    I was wondering if you could help me with a question. My partner and I are in the process of building a passive solar house up near Darrington. The Washington Energy code requires that we install windows with a U-factor of 32. These are low-e windows since they’re the only ones with a low enough U-factor. But they also block some amount of the solar heat gain. I’m wondering how the fact that the windows are designed to block heat gain will effect the passive solar heating potential of our design. Being a designer I thought you might have some ideas on that. I understand that they have to be installed to meet the state requirements. Do you make any concessions to the low-e windows blocking heat gain? I already wrote to NFRC, but the reply didn’t really address my question so I was hoping you could help.
    Thanks very much,