Fences shall be permitted on semi-detached dwelling lots. They shall not be permitted between the principal building and any abutting street line. Fences located beyond the front yard shall be permitted provided they do not exceed five feet in height. A fence of up to six feet in height shall be permitted along the common property line separating two semi-detached dwellings where the buildings adjoin, and such six foot height limit shall apply to the first 12 feet of fencing extending along the dividing property line from the principal building. Fencing shall be permitted on the property line with the permission of the adjoining property owner, and where such fencing is located on the property line, it shall be finished on both sides. Where permission of the adjoining property owner is not secured, the fence shall be placed no closer than six inches to the property line, with the finished side out. If fencing is proposed on a portion of a lot with an easement, permission shall be secured from the party with easement rights. Fencing shall be of a type which will allow for the free flow of surface stormwater.