Oriented Strand Board (OSB) is a type of composite wood board made with angled strands of wood compressed and attached using adhesives of some kind, usually formaldehyde based adhesives. Formaldehyde-containing OSB is regulated by governments for its toxic formaldehyde gas emissions, but these emissions are difficult to track in the places where OSB is most often used, including construction sites and furniture manufacturing facilities.

This project aims to replace formaldehyde-based resins in OSB with calcite formed by the bacteria Bacillus megaterium. Currently used as an environmentally friendly alternative to cement in concrete, calcite precipitated by bacteria, including Bacillus megaterium, is capable of acting as an adhesive between sand and rock particles. Because this adhesive requires little energy usage, is biodegradable, and does not emit hazardous gasses, this project attempts to use this process to attach pieces of wood into an alternate type of OSB.

In this project, Bacillus megaterium is grown in liquid media, given calcium acetate and urea in order to stimulate calcium carbonate formation, and placed between wooden sticks. The temperature of the procedure, type and texture of the wood, and stresses placed on the wood during the procedure are varied. Through the many variations, observed adhesion between certain samples of wood was created.

While the methods used, designed to mirror those used for concrete formation, may not be most effective for wood adhesion, strong OSB formation may still be better achieved using different bacteria species, wood species, and media additives in the future.