24-521 - Front setbacks in districts where front yards are required LAST AMENDED 3/22/2016 R1 R2 R3 R4 R5 In the districts indicated, except R5D Districts, where #front yards# are required, the front wall or any other portion of a #building or other structure# shall not penetrate the #sky exposure plane# set forth in the following table: MAXIMUM HEIGHT OF FRONT WALL AND REQUIRED FRONT SETBACKS Height above #Sky Exposure Plane# District #Front Yard Line# Slope over #Zoning Lot# (expressed as a ratio of vertical distance (in feet) to horizontal distance) On #Narrow Street# On #Wide Street# Vertical Horizontal Vertical Horizontal Distance Distance Distance Distance 25 1 to 1 1 to 1 R1 R2 R3 35 1 to 1 1 to 1 R4 R5 SKY EXPOSURE PLANE R1, R2, R3, R4, R5 Districts