City of San Mateo Law Library
City of San Mateo Municipal Code.

27.18.060 FLOOR AREA RATIO.

The floor area ratio of buildings and structures on a parcel shall not exceed the following limitations:

Districts Maximum Floor Area Ratio
R1-A 0.4 for parcels of less than or equal to 10,000 square feet plus 0.2 for additional parcel area over 10,000 square feet.
R1-B and R1-C 0.5 for parcels of less than or equal to 6,000 square feet plus 0.2 for additional parcel area over 6,000 square feet.

In no case shall more than 6,000 square feet of total floor area be permitted per parcel in residential use.