Track 2: Sustainability and Conservation of Built Heritage in the Americas
Randy Van Straaten, P. Eng
Senior Research EngineerSenior Research Engineer
RDH Building Science Laboratories
Annabelle Radcliffe-Trenner, AIA, RIBA, LEED AP
Principal
Historic Building Architects LLC
Hygrothermal computer models are being used by preservationist and engineers with forensic work or for analyzing decay risks associated with exposure or assembly change. A key parameter within these models are material properties. There is little of such data for historic clay bricks available in publications. This paper presents an archive of clay brick material properties for over 450 clay bricks from 60 northeastern North American buildings as old as 1830. The material properties include dry density, water absorption coefficient, 80% relative humidity moisture content, free water saturation, vacuum water saturation, water vapor permeance, and critical freeze thaw water saturation. This archive also includes the vintage of bricks, identifying frog labels, location within the wall, and geographic location of the buildings. Basic material property data is fundamental to the quality of analysis being provided in the industry and sharing this data is important to the progress of developing these simulation tools for applications in building preservation industry. Beyond applications for simulation models, a number of interesting insights can be drawn from examining data range and correlations. What are the typical characteristics of face relative to fill brick: are they typically “better” material or selected based on aesthetics. How have the material properties of clay brick evolved over the past 180 years. Can characteristics observable during field inspection be used to predict material properties which otherwise require laboratory measurement. These and other finding from analyzing the dataset will be shared and we look forward to insights other experts can draw from our archive.