(A) The following shall be considered as permitted encroachments on setback and height requirements, except as herein provided:
(1) In any yard. Posts, off-street open parking spaces, flues, leaders, sills, pilasters, lintels, cornices, eaves, gutters, awnings, open terraces, service station pump islands, open canopies, steps, chimneys, flag poles, ornamental features and fences, and all other similar devices incidental and appurtenant to the principal structure, except as restricted elsewhere herein;
(2) In side and rear yards. Bays not to exceed a depth of three feet or contain an area of more than 30 square feet, fire escape not to exceed a width of three feet. Breezeways, detached outdoor picnic shelters, open arbors and trellises may extend to within five feet of a side or rear lot line; except that, no structure shall exceed 500 square feet. Covered porches may extend 20 feet into the rear yard, but not closer than ten feet from the rear lot line, and must meet shoreland standards; and
(3) Height limitations. Height limitations shall not apply to barns, silos and other non-residential farm structures; to church spires, belfries, cupolas and domes; monuments; chimneys and smokestacks; flag poles, public utility facilities; transmission towers of commercial and private radio broadcasting station; television antenna, private ham radio towers and parapet walls extending not more than four feet above the limiting height of the building, except as provided in municipal airport zoning provisions.
(B) In no event shall off-street parking space, structures of any type, buildings or other features cover more than 50% of the lot area resulting in less than 50% landscaped area in Residential Districts.