Question

This product was developed originally in 1905 by Gustav Carlson for the Lewis & Clark Centennial Exposition in Portland, Oregon. It was not until 1935 that this now-common building material became widely accepted. What product is this and what happened in 1935?

Answer

In 1905, Gustav Carlson glued together thin sheets of softwood veneer using an adhesive rendered from animals to form the first plywood. Unfortunately, his glue became so rank that expo exhibitors had to periodically leave the building for fresh air. Over the years various adhesives were tried but often lacked the necessary strength or water resistance. It wasn't until the production of phenol-formaldehyde in the mid-1930s that plywood became widely accepted. In this century, the green-building movement has stimulated the availability of plywood made with formaldehyde-free resins that meet modern performance criteria.