Minimum lot area and lot width regulations in any zone shall not apply to repeater, booster, transformer or switching stations or dial offices.

In any district wherein a single-family dwelling is permitted, such dwelling may be permitted on any lot or parcel which is of official record by deed or a subdivision duly recorded in the plat records of Carroll County as of the effective date of this chapter, provided that:

If attached to or directly adjoining the main building, a carport or a one-story open porch, with a roof, may extend into the required front, side or rear yard not more than 25% of the minimum required yard depth.

If attached to or directly adjoining the main building, a one-story open deck without a roof may extend into the required rear yard not more than 50% of the minimum required yard depth.

Projections, such as bay windows, chimneys, entrances, vestibules, balconies, eaves and leaders, may extend into any required yard not more than four feet, provided that such projections (except eaves) are not over 10 feet in length.

Fences and walls shall be exempt from building line and yard requirements unless they are obstructions to vision.

No deck, porch, carport, or other projection shall be allowed in any easement area.

The allowable projection into any yard shall be calculated by measuring the minimum distance from the applicable property boundary to the point of maximum projection into the yard. No additional allowance shall be granted for cantilevered decks, stairs or other appurtenances to any projection.

Building height limitations shall not apply to water tanks, barns, windmills, silos or other accessory farm structures; or to belfries, steeples or spires; electric or communication poles or towers, electric generating plants, electric transforming or switching equipment or radio, television or radar towers; chimneys or smoke stacks; flagpoles, fire or observation towers, cupolas, domes, monuments, penthouses or roof structures for housing stairways; or tanks, ventilating fans, air-conditioning equipment or similar equipment required to operate and maintain the building. No penthouse or roof structure shall have a total area greater than 25% of the roof area, nor shall such structure be used for any purpose than a use incidental to the main use of the building.

In any R district, the height of a principal structure may be extended to 3 1/2 stories, but not over 50 feet, if each side yard is increased in width 1/2 foot for each additional 1 foot of height above the normal maximum limit. In any B district, the height of a principal structure may be extended to 4 stories, but not over 55 feet, if each side yard is increased in width 1/2 foot for each additional 1 foot of height above the normal maximum limit.

On any lot where the average finished slope adjoining the building exceeds a grade of 7%, one story, in addition to the number permitted in the zone in which such lot is situated, shall be permitted on the downhill side of any building erected, but the building height limit shall not otherwise be increased above that specified for the zone.

In any zone where public or quasi-public buildings are permitted, such buildings may be erected to a height of 120 feet, but the minimum front, rear and side yards shall be increased one foot for each foot of height above the limit established for the zone in which the building is erected.