Side Yard. In any district, open, uncovered, raised porches, landing places or outside enclosed stairways may project not closer than three feet (3′) to any side lot line, except in the R-1 (single-family residential) district where such projections may not exceed one foot (1′) into any required ten foot (10′) side yard. Exception: Exterior unenclosed stairways shall meet side yard setbacks of the zoning district in which they are located.