Chapter 27.18 R1 DISTRICTS—ONE FAMILY DWELLINGS 27.18.010 PURPOSE. 27.18.020 PERMITTED USES. 27.18.030 SPECIAL USES. 27.18.035 SUBSTANTIAL REMOVAL OF EXISTING RESIDENCE. 27.18.040 PARCEL SIZE STANDARDS. 27.18.050 BUILDING HEIGHT AND DAYLIGHT PLANE. 27.18.060 FLOOR AREA RATIO. 27.18.070 Front Yard 27.18.080 Side Yards 27.18.090 REAR YARD. 27.18.100 STRUCTURES AND BUILDING PROJECTIONS IN REQUIRED YARDS. 27.18.110 OFF-STREET PARKING. 27.18.115 San Mateo Park Planning Area 27.18.120 CEMETERIES, MAUSOLEUMS, AND COLUMBARIA.