The 2nd American Historic Cement Conference
New York, NY
March 31 - April 1, 2011
Link to the First American Natural Cement Conference Page
The American Historic Cement Conference convened in New York City on March 31, 2011, attended by 117 participants from the United States and Canada. Edison Coatings, Inc. was pleased to join other corporate sponsors in supporting this unique educational event. The following is an overview of program highlights:
DAY ONE: AMERICAN MUSEUM OF NATURAL HISTORY AND CENTRAL PARK
Moderators: Jeffrey Chusid, Cynthia Field
Richard Pieper (Jan Hird Pokorny Architects and Columbia University) provided the keynote address, tracing the history of concrete materials and construction methods, and changes in technology from 1850 to 1920.
John Fidler (Simpson Gumpertz Heger and formerly English Heritage)provided a critical view of preservation philosophy in the context of a built environment that has undergone alterations on an almost continuous basis.
John Wathne (Structures-North Consulting Engineers and ASTM Task Group Chairman C12.03.03 Historic Mortars) discussed the upcoming changes in ASTM C1713 Historic Mortars, and provided examples of how the new standard could be used in preparing project specifications for use of historic mortars.
Denis Brosnan (Clemson University) presented the results of a study performed with the National Park Service on repointing mortars used over past decades at Fort Sumter National Monument. The study included a conclusion that the portland cement mortars used in the latter half of the 20th Century are the direct cause of significant masonry damages at the fort. Rosendale Cement, used in the 2008 repointing campaign, was identified as most compatible with the original natural cement-based masonry construction.
Jeffrey Chusid (Cornell University, Society for the Preservation of Historic Cements), presented a paper on the textile block houses of Frank Lloyd Wright, and the inherent defects in Wright’s concrete design mixes that have led to their deterioration.
Tim Allanbrook and Kyle Normandin (WJE Associates) discussed the challenges associated with the restoration of the historic south range of the American Museum of Natural History, and the process leading to the decision to restore in-kind using Rosendale Cement. The presentation was followed by a facade tour of the restored museum.
Afternoon tours included historic cement sites in Central Park.
Kate Burns Ottavino (A. Ottavino Co.), Frederick Basch (Architect) and Christopher John Gembinski (Building Conservation Associates) led a tour and discussion of the historic Central Park Police Precinct, undergoing major restoration and updating. Rosendale cement mortar was used in the restoration of the historic 1870 stonework, replicating the original historic mortar.
Matt Reiley (Central Park Conservancy) led a tour of the Bethesda Arcade and Terrace. Rosendale Cement mortars played a small role in the restoration of the Arcade’s sandstone columns, which in turn are overshadowed by the Arcade’s spectacular historic ceiling, composed of 16,000 hand crafted Minton tiles.
DAY TWO: GOVERNOR’S ISLAND
Moderators: Jack Healy, Leya Edison
The second day program included presentations, a workshop and site tours:
Norman Weiss and Jennifer Schork (Integrated Conservation Resources) presented results of a study of the properties of ordinary lime and hydraulic lime mortars, and demonstrated the use of the Vicat needle for determining setting time. Concerns were voiced over the high strengths being observed with Type N cement-lime mortars, often achieving strengths in excess of 3000 psi.
Michael Edison presented the results of a study by Chad Lausberg (Edison Coatings, Inc.) on the strengtth development profiles of 11 natural cement and natural cement-lime mortars, prepared at varying proportions to correspond with results of various historic mortar analyses. The wide range of proportions found in historic mortars, and the frequent use of very cement-rich mortars without lime were highlighted.
John Harry (John Harry Restoration Services) led a workshop in matching textures and visual appearance in historic concretes and stuccos. His work at College of Charleston Randolph Hall (natural cement stucco) and New Orleans Lakefront Airport (portland cement stucco) were featured. Everyone then got to try their hands at mixing natural cement stucco, and at working the surface to achieve different textures.
Dede Nash and Mark Kanonik (Einhorn Yaffee Prescott) presented a history of the construction of Castle Williams on Governor’s Island, and discussed the unusual mortars discovered there from the 1812 era of construction.
Judy Jacob (National Park Service)and Rich Lattanzi led a tour of the restoration work at Castle Williams.
THE SOCIETY FOR THE PRESERVATION OF HISTORIC CEMENTS, INC. ANNOUNCED THAT THEIR NEXT CONFERENCE WILL BE HELD in MARCH, 2016.