Any existing building or structure erected prior to the adoption date of this Title which does not conform to the applicable yard regulations of this Zoning Ordinance, may continue without need of a variance authorized by the Board of Zoning Appeals, provided that the building or structure does not encroach upon any public right-of-way or public utility easement.
(a) Additions to said non-conforming buildings on lots with an area of not more than 7,500 square feet, which are erected in accordance with § 17-1007(a)(4), § 17-1107(a)(4), or § 17-1207(a)(4); § 17-707(a)(3); § 17-1007(b)(3), § 17-1107(b)(3) or § 17-1207(b)(3), shall also be permitted to continue.
(b) Buildings which do not conform to the applicable yard regulations of this Zoning Ordinance are subject to the provisions of § 17-3102(b).