A. Assignment of Solar Factor. Land divisions which create new lots shall be designed to permit the location of a 21-foot high structure with a setback which does not exceed 50 percent of the lot's north-south lot dimension pursuant to the following standards.
1. Lots having north facing (negative) slopes of less than 15 percent (e.g., ten percent) and which are zoned for residential uses shall have a north-south lot dimension equal to or greater than that calculated by using Formula I in 18.4.8.020.A.1.
2. Lots having north facing (negative) slopes equal to or greater than 15 percent (e.g., 20 percent) or are zoned for non-residential uses shall have a north-south lot dimension equal to or greater than that calculated by using Formula II in 18.4.8.020.A.2.
B. Solar Envelope. If the applicant chooses not to design a lot so that it meets the standards set forth in subsection A, above, a solar envelope shall be used to define the height requirements that will protect the applicable solar access standard. The solar envelope and written description of its effects shall be filed with the land partition or subdivision plat for the lot(s).
C. Lots Affected By Solar Envelopes. All structures on a lot affected by a solar envelope shall comply with the height requirements of the solar envelope.