If, at the time of passage of this chapter, a lot or the aggregate of contiguous lots of land parcels held in a single ownership has an area of dimension less than required for the zoning district in which the property is located, the lot or aggregate holdings may be occupied by any permitted use in the district, subject to compliance with all other requirements of the district; provided, however, that the use of a lot in any residential district which has an area deficiency shall be limited to a single-family dwelling.

If there are dwellings on both abutting lots with front yards of less than the required depth for the district, the front yard for the lot need not exceed the average front yard of the abutting dwellings. If there is a dwelling on one abutting lot with a front yard of less than the required depth for the district, the front yard need not exceed a depth 1/2 way between the depth of the abutting lot and the required front yard depth.

Projections such as chimneys, spires, domes, elevator shaft housings, aerials, other than freestanding, flagpoles and other similar objects not used for human occupancy are not subject to the building height limitations of this chapter; except, however, if the provisions or requirements of the Airport Overlay District apply, the exceptions granted in this section no longer are in force.