Nettleton v. Zoning Board of Adjustment

*47 OPINION

LAMB, Justice.

This zoning appeal requires us to clarify the conceptual basis for our decision reported as Yocum Zoning Case, 393 Pa. 148, 141 A.2d 601 (Pa. 1958).

Appellants Elvidio Grande and Marianne DePlacido (Landowners) own an improved lot in the Seventh Ward of the City of Pittsburgh (City) known as 5301 Fifth Avenue (Property) in an RM-3, Residential Multi-Unit, Moderate Density zoning district as defined and regulated by the Pittsburgh Urban Zoning Code (Code). The Property is improved with a commercial one-story building seventeen feet in height with twenty-two basement…