California Code, Government Code - GOV § 66473.1

(a) The design of a subdivision for which a tentative map is required pursuant to Section 66426 shall provide, to the extent feasible, for future passive or natural heating or cooling opportunities in the subdivision.

(c) In providing for future passive or natural heating or cooling opportunities in the design of a subdivision, consideration shall be given to local climate, to contour, to configuration of the parcel to be divided, and to other design and improvement requirements, and that provision shall not result in reducing allowable densities or the percentage of a lot that may be occupied by a building or structure under applicable planning and zoning in effect at the time the tentative map is filed.

(d) The requirements of this section do not apply to condominium projects which consist of the subdivision of airspace in an existing building when no new structures are added.

(e) For the purposes of this section, “feasible” means capable of being accomplished in a successful manner within a reasonable period of time, taking into account economic, environmental, social and technological factors.