(a) In a Class U1 or U2 District, every residential building erected shall have a rear yard.
(1) In a Class U1 District, the least dimension of the rear yard shall be at least 15% of the mean depth of the lot, but such least dimension need not be more than 30 feet.
(2) In a Class U2 District, the least dimension of the rear yard shall not be less than one-half of the height of the building.
(3) Forty percent of the area of the rear yard in a Class U1 or U2 District may be occupied by a one-story accessory building not more than 15 feet in height. Such an accessory building shall not be closer than 18 inches to any property line.
(b) In a Class U3, U4 or U5 District where the rear line of the lot adjoins a Class U1 or U2 District, every building erected shall have a rear yard. The least dimension of such yard shall be at least 10% of the mean depth of the lot, but such least dimension need not be more than 20 feet, provided that such least dimension shall in no case be less than one-fourth of the height of the building.
(c) In a Class U6 District where the rear line of the lot adjoins a Class U1 or U2 District, every building erected shall have a rear yard of at least 25 feet.
(Ord. 4761, passed 11-17-1953; Ord. 5547, passed 4-21-1964)