If substantial new construction occurs on a preexisting developed site within the C, M, O or PF, MED, MX or RM zone, or on a site containing any non-single-family residential use within an RS zone, wherein parking, landscaping, signage or fencing do not conform to current municipal code standards, said nonconforming parking, landscaping, signage or fencing shall be brought up to code as determined by the impacted area of redevelopment, defined by the scope of work (i.e., if the proposal would modify or rebuild areas of the site that do not conform to current code standards such proposal shall be in conformance with the applicable code standards applying to that area of work). Major changes of use to preexisting structures (e.g., residential to commercial conversions) shall be required to meet current parking and landscaping codes regardless of the dollar value of any improvements. Any code-required landscaping shall not be required if its provisions are prohibited by location of a preexisting structure or would cause the amount or dimensions of on-site parking, including access drives, to not meet current standards.