Ensuring Durability with Stone Restoration Techniques—Critical Decisions for Common Repairs

This presentation initially took place at the 2021 Convention in Phoenix, Arizona

Architects, engineers, and preservationists have been specifying restoration repairs of stone masonry and cladding for decades. Execution of these repairs has fallen to craftsmen with a range of stone masonry experience with often inadequate or non-existent guidance from the practitioners who often lean on general industry practices. While most professionals will agree on many of the basic design principles for commonly applied repairs, each project has unique parameters that can affect the final repair design and its ultimate service life. This exploration is aimed at design professionals, as well as building owners, managers, and engineers tasked with maintaining buildings constructed of stone masonry or stone cladding. It is intended to summarize best practices for designing and implementing repairs for stone wall systems, as well as to identify the key decision points that influence the type of materials and repair procedures that we use to optimize durability. It will also challenge some commonly held beliefs regarding popular material choices and repair techniques, plus highlight how, in some instances, minor changes in approach can make significant differences in repair performance. This presentation is given at an intermediate level; some prior knowledge of exterior wall systems and stone masonry is recommended.

Matthew Farmer, PE
Wiss, Janney, Elstner Associates | Tampa, FL

Matthew Farmer is a principal investigator on evaluations of buildings and monuments, concentrating his practice in the areas of masonry building enclosure systems’ engineering, design, investigation, analysis, and repair. Projects include institutional and commercial, as well as numerous historic landmarks. Farmer received a bachelor of science in architectural engineering and a bachelor of environmental design from the University of Colorado; and a master of civil engineering from Cornell University. He is a registered professional engineer in Washington, DC, Maryland, and Virginia, plus an active member of ASTM C18 (Dimension Stone), ASTM C27 (Cast Stone), and The Masonry Society.