Studies conducted at the federal government’s Oak Ridge National Laboratory (ORNL) show that walls made of EIFS (Exterior Insulation and Finish Systems) provide “superior moisture and temperature control” as compared to several other common types of wall construction.

The studies were funded by the U.S. Department of Energy and the EIFS trade group, EIFS Industry Members Association (EIMA).

Still underway, the studies compare EIFS with walls made with brick, stucco, and cement fiber board siding. A total of 15 configurations of wall cladding materials were incorporated into a specially constructed building in Charleston, S.C., for comparison and evaluation over a period of three years. The cladding materials were fitted with sensors to record moisture content, humidity, temperature and other variables. Field data are being used to create a computer simulation intended to predict wall performance of the subject variables, called a hygrothermal model. A summary of the study’s initial findings was issued recently by Achilles Karagiozis, Ph.D., of ORNL’s Building Envelope Group. The summary asserts that the research is “useful … in demonstrating the superior moisture and temperature control performance of EIFS as compared with other types of exterior claddings.” It also states “EIFS drainage assemblies with vertical ribbons of adhesive provide a drainage path and air space that contributes positively towards the hygrothermal performance of the walls.”

Highlights of the study are included in a memo, titled “The Hygrothermal Performance of Exterior Wall Systems: Key Points of the Oak Ridge National Laboratory NET Facilities Research Project.” The memo can be viewed at this website: