No so-called dead-end streets will be approved for dedication except where physical conditions make the extension of such a street impractical. In such cases a dead-end street may be approved, provided that adequate turning space for vehicles is placed at the dead-end.
Turning space shall be of sufficient size to provide for a paved circular roadway of at least twenty feet in width, the inside radius of which shall be at least twenty-five feet.
(1955 Code. §1103.10)