After the effective date of this section, any building or facility which would have been subject to this chapter but for the fact it was constructed prior to November 13, 1968, shall comply with the provisions of this chapter when alterations, structural repairs or additions are made to such building or facility. This requirement shall only apply to the area of specific alteration, structural repair or addition and shall not be construed to mean that the entire structure or facility is subject to this chapter.
Ca. Gov. Code § 4456