A roof truss is a pre-engineered, factory-built triangular structural framework that supports the roof, installed as a complete unit rather than built piece by piece on-site.
Trusses have largely replaced traditional rafter-built framing in new residential construction because they're engineered for precise load calculations, faster to install (craned into place as complete units), and often allow longer spans without interior load-bearing walls. They're generally not intended to be modified on-site without an engineer's review, since altering a truss can compromise its designed load path.
Only with an engineer's review — trusses are designed as a complete load-bearing system, and cutting or altering a truss member without proper reinforcement can seriously compromise structural integrity.
Get matched with licensed contractors near you.