Roof and Floor Truss Systems

Open-web Floor Joists

Parr Lumber Open-web Floor Joists, represent a significant and rapidly growing type of floor truss system used in homes today. Our Open-web joist consists of a 2×4 wood top and bottom chord connected with metal webbing called a Posi-Strut (®). One main advantage of the Open-web system over dimensional lumber or I-joists is that the open spaces between them allow for easier routing of utilities (electrical, plumbing, HVAC, etc). Open-web Floor Joists also provide greater strength than standard I-joists allowing for longer spans and greater design flexibility.

Benefits of the Parr Lumber Open-Web System

  • The ability to have HVAC in controlled environment reducing energy cost and greatly improving HVAC efficiencies
  • Reduced HVAC installation costs (shorter runs, smaller trunk lines, etc)
  • Greater clear spans for design flexibility
  • Possible reduction of strip footings, pony-walls and /or labor posts
  • Wide nailing surface for easier handling, nailing/screwing while reducing the risk of “squeaks” caused by insecure decking attachment
  • Easy plumbing and electrical installation
  • Factory manufactured to exact specifications

NSC (Northwest Structural Components)

The Future of Framing is here