Surface microbiomes of cross-laminated timber before and after wetting

Structural mass timber products, such as cross-laminated timber (CLT), represent a sustainable alternative to the negative environmental impacts of concrete and steel in low- to mid-rise construction. In particular, CLT is well-suited for use in the growing US outpatient healthcare real estate market, since exposure to natural materials such as wood has been shown to have health benefits, and use of CLT can reduce costs by combining structural capabilities with a desirable finish aesthetic. However, architects and developers have encountered market barriers related to the difficulty of sanitizing wood surfaces and their potential for mold growth after wetting. The goal of this study was to examine how physical and chemical qualities of CLT affect microbial survival and growth under dry and several different wetting conditions, representing a range of duration and severity of moisture exposure.