Bend Solar Work Group Goes on Winter Solstice Field Trip

During a the midday hours of Friday, December 21st members of the Bend Solar Work Group met in northwest Bend to observe the “solar shading” effect various newly constructed homes have on each other.  This field trip is part of the ongoing and partially volunteer effort to draft a new solar building code for the City of Bend.

The group chose this particular day because it was a workday closest to Winter Solstice; the day the sun rises to its lowest point during the year.  This is the most commonly used benchmark day that many cities use for the “solar fence” or “solar setback” approach to their building codes as it relates to active and passive solar construction and solar access rights.  Cities choose this day because it has the least amount of solar radiation that can potentially be produced by the sun and it’s the day that nearby buildings and natural features (typically trees) can block the most solar radiation with their shadows.

The group was blessed with a beautiful but cold day for this field trip.  The sky was virtually without clouds so it was easy to observe firsthand the sun shadows that the houses and trees cast upon nearby homes and vacant building lots.  The bright sunlight allowed the group to easily see the detrimental effects solar ignorant design and construction – especially of rooflines – had on neighboring houses. In addition to the simple visual appraisal a “Solar Pathfinder” was utilized to add to the data collection.  This relatively small, totally manual device has been used to provide solar site analysis since it was originally invented over 30 years ago.
Almost all of the homes viewed were fairly closely spaced together in an attempt to create “urban density” but were too often oriented in a north-south direction and of varying heights that created massive solar energy shadowing.  Unfortunately, most of the houses observed would not be able to qualify for State of Oregon passive solar credit even with major remodeling.

Although no absolute decisions were made during this outing many excellent ideas were offered and discussed.  The information gathered from this field trip will be invaluable during future indoor meetings as the group tackles the solar access building code issues for both infill construction and new development.

The Bend Solar Working Group began its meetings starting in early September 2007 and has held meetings averaging every few weeks since then. The group is made up of members of the City of Bend’s planning department, a Bend City Councilor, architects and builders who are specialists in active and passive solar design and construction, a well-known and respected “environmental” attorney, a State of Oregon DLCD employee, Bend-based sellers and installers of active and passive solar energy systems and one interested citizen.  More background information on the group can be found at “Bend Building Code Goes Solar?“

Bend Building Code Goes Solar?

Like many of the cities in the U.S., Bend is attempting to deal with the challenges brought about by the increasing use of solar energy in residential and commercial construction. The following excerpts are from an article that originally appeared in High Country News and was reprinted in the Source with permission and includes additional reporting by the Source staff.

When the Joneses go solar: As photovoltaic panels pop up on rooftops, planners feel the pain
by Isabelle Groc – August 8, 2007

Roughly a year after dropping the city’s sunlight ordinance, Bend planners are taking a second look at ways the city can encourage new and existing property owners and developers to take advantage of Mother Natures most powerful and abundant source of power.

City of Bend planner Wendy Robinson said she is putting together an informal group of interested parties to discuss how the city can make it easier for people to tap solar. The work, which will likely begin this fall, will examine options like requiring developers to align streets with south facing houses and possibly resurrecting rules that could limit things like second story additions in existing neighborhoods where they cast a long solar-sucking shadow onto an adjacent property.

While solar ordinances are notoriously hard to enforce, they are also popular for reasons of aesthetics and energy. In the case of Bend, the city was asked by the state to revisit the solar issue as part of a larger legal challenge of the development code. [The legal challenge was issued by Bend attorney Paul Dewey who filed an objection with the State of Oregon regarding Bend’s poorly written solar access protection ordinances.]