The Pros and Cons of I-Joists

摘要

We have all read about or heard of the dangers of engineered wood joists-or I-joists-when exposed to fire, but they don't need to be on fire to degrade. Developed in 1969, I-joists have become a construction staple because of their economic value and ability to shoulder large loads over large spans. Originally constructed of a plywood web and solid flanges (chords), the flanges were replaced with laminated wood in 1977. The switch to orientated strand board (OSB) webs occurred in 1990.