Design Aids

Posi-STRUT Floor, Purlin and Roof Trusses

The GANG-NAIL Posi-STRUT system is a light, economical method of providing large clear spans in rafter, purlin and floor joist situations. Frames and supports can be spaced further apart to facilitate open spaces below.A GANG-NAIL Product, marketed by MiTek New Zealand Ltd

The heart of the Posi-STRUT truss is the GANG-NAIL Posi-STRUT web. This is a folded metal web with nail plates at the pointed ends. The metal web is pressed onto timber chords to form a parallel chord truss.

Benefits of using Posi-STRUT

  • Services (electrical, plumbing, vacuum systems) are easily run through the trusses without the need to drill holes, weakening the floor.
  • Light to lift and fast to install.
  • Greater spans for a given depth than solid timber joists.
  • Camber is built in, resulting in a flat ceiling line.
  • Shrinkage problems through using green timber are eliminated.
  • Strongbacks run through the trusses, providing more effective load sharing than solid nogging.
  • The ceiling can be fixed directly to the underside of the Posi-STRUT trusses, saving time and materials.
  • Competes with other floor systems on price

For further information, including full selection charts and usage details, go to the MiTek website,

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