What is Truss in Staging and Lighting?

Truss is a lightweight metal framework, usually aluminium, used to hang lighting, speakers, screens and set pieces above a stage or to build ground-supported structures. It is made in sections that bolt or pin together, so it can be built into straight runs, squares, circles and complex shapes for each show.

How truss is used

A truss system is planned and built in five steps:

  1. Design: the lighting or production designer draws the truss layout and what will hang on it.
  2. Calculate loads: the rigger checks the weight on each section and hanging point against the manufacturer's load tables.
  3. Assemble: crew build the truss on the stage floor and hang the equipment.
  4. Lift: the truss is raised on chain hoists from the roof, or on towers in a ground support system.
  5. Check and secure: heights, levels and safety connections are checked before the show.

Truss plans, load calculations and rigging plots need to be shared with venues and riggers, which teams do with documents in Crescat.

Flown truss vs ground support

Flown truss hangs from the venue's roof structure on chain hoists. Ground support stands on towers and bases, and is used outdoors or where the roof cannot take the weight. Festival stages often use ground support or a full stage roof system.

Common types of truss

  • Box truss: four main tubes, the most common for touring
  • Triangle truss: three tubes, lighter for smaller loads
  • Ladder truss: two tubes, for light loads and set pieces
  • Circular and curved truss: for shaped designs
  • Pre-rigged truss: lights stay fitted inside for fast touring
  • Towers and bases: for ground support

Frequently asked questions

How much weight can truss hold?

It depends on the type, size, span and how it is supported. Every manufacturer publishes load tables, and a competent rigger must check them for each design.

What sizes does truss come in?

Common sizes are named by their width, such as 290 mm (about 12 inches) and 390 mm or 400 mm. Bigger truss spans further and carries more.

Who is allowed to rig truss?

Trained and competent riggers. Hanging loads over people is high-risk work, and venues usually require their own rigger to approve the plan.

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