Wherever any room in which persons live, sleep or work, except stores and storage rooms, cannot be reasonably and exclusively lighted and ventilated from a street or from a side yard or rear yard as required above, a court conforming with the provisions of this section shall be required, on which such room shall open. A court is any open space on the lot other than a setback front yard, rear yard or side yard. An outer court is one, which extends to a street, a front yard or a rear yard. An inner court is any other court. The width of the court is its least horizontal dimension including the width or any open space within the lot on which its long side abuts.

No inner court shall have a length, which is less than twice its width. No outer court shall have a length, which is greater than four times its width. No court shall have an opening less than its width. No court need extend below the lowest story, which it is required to serve. Widths of courts shall not be less than as follows:

In any dwelling district or apartment district. No accessory building shall be permitted within any court.

Except as herein specified, all yard and courts shall be open, unobstructed to the sky.

Cornices and eaves may project not more than three (3) feet over any front or rear yard; and over any side yard to an extent not exceeding one-third of the width of such yard or court and not exceeding two (2) feet except within five (5) feet of the front wall, where they may project in any case not more than three (30 feet. Sills, leaders, belt courses and ornamental features may project not more than six (6) inches into or over any yard or court. A bay window not exceeding ten (10) feet in width may project into a front, side or rear yard not more than three (3) feet and not more the one-third of the width of the side yard in any case and an open fire-escape may not thus project more than five (5) feet, provided neither shall project within five (5) feet of any side lot line.