(a) The following uses and structures constitute obstructions which are nevertheless permitted in any required yard as follows:
(1) Awnings and canopies;
(2) Window air conditioners;
(3) Chimneys which project no more than three feet into a yard and which have a horizontal area not in excess of two percent of the actual area of the yard;
(4) Eaves, gutters or downspouts which project no more than sixteen inches into a yard;
(5) Fences, which shall have a maximum height of eight feet and which can be of any style except chain-link and stockade style fences;
(6) Flagpoles;
(7) Steps, excluding fire escapes;
(8) Walls not exceeding eight feet in height and not supporting or covered by a roof; and
(9) Accessory off-street parking areas which are not covered by a structure.