Civ. Code, § 4747

(a) Any covenant, restriction, or condition contained in any deed, contract, security instrument, or other instrument affecting the transfer or sale of any interest in a planned development, and any provision of a governing document, is void and unenforceable if it effectively prohibits or unreasonably restricts an eligible housing development project from using the floor area ratio standards authorized under Section 65913.11 of the Government Code.

(b) This section does not apply to provisions that impose reasonable restrictions on an eligible housing development that do not make the implementation of the floor area standards authorized in Section 65913.11 of the Government Code infeasible.

(c) For purposes of this section:

(1) “Eligible housing development project” means a housing development project that meets the requirements of subdivision (b) of Section 65913.11 of the Government Code.

(2) “Reasonable restrictions” means restrictions that do not unreasonably increase the cost to construct, effectively prohibit the construction of, or extinguish the ability to otherwise construct an eligible housing development project using the floor area ratio standards in a manner authorized by Section 65913.11 of the Government Code.

(d) The Legislature finds and declares that the provision of adequate housing, in light of the severe shortage of housing at all income levels in this state, is a matter of statewide concern and that this section serves a significant and legitimate public purpose by eliminating potential restrictions that could inhibit the production of adequate housing.