Expansion or Enlargement of Previously Conforming Structures or of Structures on a Premises with Previously Conforming Density
San Diego Municipal Code § 127.0106
in effect§127.0106 Expansion or Enlargement of Previously Conforming Structures or of Structures on a Premises with Previously Conforming Density
(a) Proposed expansion or enlargement of a structure with a previously conforming structural envelope or of a structure on a premises with previously conforming density is permitted in accordance with Process One as follows, except that such development on a premises that contains or abuts a coastal beach or a coastal bluff edge, shall be subject to Section 127.0106(c):
(1) Where all new construction conforms with current development regulations for setbacks, floor area ratio, and structure height and does not increase the non-conformity regarding structural envelope or density;
(2) Where the proposed expansion or enlargement is necessary to incorporate required public exits or fire walls to meet public safety requirements of the California Building Code or California Fire Code for a conforming use in a previously conforming multiple dwelling unit or non-residential structure as long as the need is not one created by the proposed expansion or enlargement.
(b) Proposed expansion or enlargement of a previously conforming structural envelope within a setback, or of a structure on a premises with previously conforming density that does not meet the criteria for expansion or enlargement in accordance with Section 127.0106(a), requires a Neighborhood Development Permit decided in accordance with Process Two, which shall only be granted if the proposed expansion or enlargement meets all of the following criteria:
(1) Conforms to the setback observed by the existing structure;
(2) Complies with the floor area ratio and maximum structure height of the underlying base zone;
(3) Does not encroach into a front yard or extend outside of the developable area of the underlying base zone to within 10 feet of the front yard setback line, unless the proposed expansion or enlargement would reduce the non-conformity of existing development;
(4) Does not encroach more than 15 feet into any required side or rear yard;
(5) Does not result in a total structure length within the required yard that is greater than 50 percent of the length of the adjacent property line;
(6) Does not create any new habitable space within 3 feet of the property line;
(7) Is limited to additions at the first story level (as measured in accordance with Section 113.0261) and does not exceed the height of the existing structure within the setback;
(8) Does not result in more dwelling units than the underlying base zone allows; and
(9) Does not propose development on a premises that contains or abuts a coastal beach or coastal bluff edge.
(c) For structures located on a premises that contains or abuts a coastal beach or a coastal bluff edge, new additions or improvements to existing structures may be permitted subject to a Coastal Development Permit, in accordance with Section 126.0707, provided that all such new additions or improvements themselves do not increase the degree of non-conformity and comply with all of the following:
(1) The proposed coastal development is in conformity with the certified Local Coastal Program land use plan;
(2) The proposed coastal development does not alter more than 50 percent of the exterior walls of the structure as measured in accordance with Section 127.0111;
(3) The proposed expansion does not exceed 500 square feet, except additional floor area may be permitted in exchange for the removal or relocation of an equivalent amount of existing floor area (from the primary structure or an accessory structure) from within a required setback from the coastal bluff edge or side yard setback to a location at least 40 feet from the coastal bluff edge;
(4) The proposed expansion does not include development of a basement with building area 5 feet or more below grade or the use of caisson foundations;
(5) The proposed expansion does not result in a cumulative increase greater than 50 percent of the gross floor area of the structure, where the total expansion area is measured over time and includes the sum of all additions to the structure approved on or after October 13, 2016. The applicant shall provide evidence of the nature and extent of the cumulative changes at the time of application for any construction permit.
(6) The proposed coastal development does not rely on existing shoreline protection; and
(7) The applicant agrees to execute and record a waiver of future shoreline protection, and the execution and recordation shall occur prior to the issuance of the first building permit.
(d) In the Coastal Overlay Zone, the previously conforming status for a structure located on a premises that contains or abuts a coastal beach or a coastal bluff edge shall terminate upon:
(1) destruction, demolition, or removal of 50 percent or more of the structure’s exterior walls, on a cumulative basis, which is any destruction, demolition, or removal that has occurred on or after October 13, 2016, which shall be measured in accordance with Section 127.0111, and for which the applicant shall provide sufficient evidence of the nature and extent of the cumulative changes at the time of application for any construction permit to rebut a presumption that the development is not entitled to previously conforming status, or
(2) upon destruction, demolition, or removal of 50 percent or more of the capacity of the lateral or vertical load resisting system of the previously conforming structure, as determined by the Building Official.
Upon termination, the development standards applicable to new structures shall then apply to the entire structure.
(e) Proposed expansion or enlargement or a change in use of a previously conforming large retail establishment is subject to a Process One Construction Permit and the applicable supplemental regulations in Section 143.0355(e) except as described below. Proposed expansion or enlargement or a change in use of a large retail establishment that would result in a structure that is 100,000 or greater square feet of gross floor area and an increase in average daily trips is subject to a Site Development Permit in accordance with Section 126.0502.
(Amended 1-9-2001 by O-18910 N.S.; effective 8-8-2001.)
(Amended 11-28-2005 by O-19444 N.S.; effective 2-9-2006.)
(Amended 6-15-2007 by O-19624 N.S.; effective 7-15-2007.)
(Retitled to “Expansion or Enlargement of Previously Conforming Structures or of Structures on a Premises with Previously Conforming Density” and amended 5-5-2015 by O-20482 N.S.; effective 6-4-2015.)
(Amended 7-19-2016 by O-20672 N.S.; effective 10-6-2016.)
Source: City of San Diego Office of the City Clerk, San Diego Municipal Code and City Charter (docs.sandiego.gov PDFs)URL: https://docs.sandiego.gov/municode/MuniCodeChapter12/Ch12Art07Division01.pdf#page=8Fetched: 10/28/2026