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Ellis Schmidlapp

Thomas S. Stevenson, Jr.

William R. Hashinger







Landmarks Design Associates was a full-service architectural firm specializing in historic preservation in Western Pennsylvania. The work included rehabilitation and adaptive use of existing buildings as well as the design of new structures within existing neighborhoods and districts. The firm was founded in 1978 by Ellis L Schmidlapp and was active from 1980 through 2015.


For over thirty five years, the firm directed the historic rehabilitation of existing buildings, both modest and grand, and designed compatible new construction in historic settings. LDA received awards and honors from organizations which included the National Trust for Historic Preservation, the Pennsylvania Historical and Museum Commission, the City of Pittsburgh, and Pittsburgh History & Landmarks Foundation.


LDA’s work included single and multi-unit residential projects, educational institutions, recreational facilities, commercial buildings, religious properties, and governmental and museum properties.