The Gypsum Association has released GA-227-13, “Recommendations for the Prevention of Ceiling Cracking.” The publication outlines methodologies for mitigating cracking in large span gypsum board ceilings due to fluctuations in temperature and humidity.
GA-227-13 explains that ceiling cracks can appear at gypsum board joints when the span between framing members approaches or exceeds 15 feet. The centerline cracks can occur because materials such as gypsum board and wood framing shrink and expand at different rates due to periodical changes in moisture content (i.e. hygrometric coefficient of expansion) and temperature (i.e. thermal coefficient of expansion). To address the issue, the document details how resilient channels can reduce the occurrence of cracking.
“The methods for the use of resilient channels described in this document have been shown to be very effective in preventing ceiling cracks due to swings in temperature and moisture content of wood framing—particularly in long spans,” said Robert Wessel, Ph.D., FASTM, senior director of technical services for the Gypsum Association. “The swings usually occur during a change in season from summer to winter or in dry areas such as desert environments.”
Electronic copies of GA-227-13 are available free of charge and can be downloaded from the publications section of the Gypsum Association web site at www.gypsum.org. The document will soon be available in French to serve French speaking areas of Canada.