Truss lighting is the practice of mounting stage and event lighting fixtures on truss structures — the interlocking aluminium lattice framework used in live events, theatre, concerts and temporary venue installations. The truss provides a rigid, load-bearing platform at height for lighting rigs, moving head fixtures, LED bars and other equipment that needs to be positioned above the stage or performance area.
What Is Truss and How Does It Work
Stage truss is made from aluminium tube sections welded into a triangular or square cross-section lattice. The geometry of the lattice distributes load across multiple members, providing strength at low weight — a key requirement for temporary structures that need to be carried, assembled and dismantled regularly. Truss sections bolt or clamp together end-to-end using conical connector systems, allowing long runs of any length to be assembled from standard 1m, 2m or 3m sections. Lighting fixtures attach to the truss via c-clamps (also called barrel clamps or hook clamps) that grip the tube of the truss structure.
Common Truss Lighting Configurations
The most common configuration for a small to medium venue is a front lighting truss — a single run of truss suspended across the front of the stage at 3–5 metres height, carrying wash and profile fixtures that illuminate the performers from the front. A backlight truss behind the performers creates separation and depth. A full rig for a larger production adds side trusses, overhead grid positions and possibly moving truss (automated systems that raise and lower the entire structure). For purchasing guidance, see the buyer's guide. For beginner guidance, see the beginner's guide.
Safety and Load Ratings
Every truss section has a rated maximum load — the weight it can safely carry per metre of span. This rating must be respected absolutely; overloading truss causes structural failure. The weight of all fixtures, cables, clamps and accessory equipment must be calculated and compared against the truss rating before any rig is assembled. Additionally, the rigging points from which the truss hangs (ceiling beams, ground supports, chain motors) each have their own load ratings. Truss lighting installation in any venue with a suspended rig requires a competent rigger who can verify the complete weight and rigging point load calculations.
Frequently Asked Questions
What is truss lighting?
It is the practice of mounting stage and event lighting fixtures on aluminium lattice truss structures. The truss holds lights at height above the stage or performance area, allowing fixtures to illuminate performers and the venue from positions that would otherwise be impossible to achieve on a temporary or touring basis.
What types of truss are used in stage lighting?
The most common types are box truss (square cross-section, four-tube construction) and triangular truss (three-tube construction). Box truss is generally heavier but provides higher load ratings per metre, making it the standard for large professional rigs. Triangular truss is lighter and cheaper, suited to smaller applications. Within both categories, tube diameter and wall thickness determine the specific load rating.
How do lights attach to truss?
Via c-clamps — also called hook clamps or barrel clamps — that grip the tube of the truss section. The fixture's mounting bracket or yoke is connected to the clamp, and a safety bond (a secondary wire or chain) connects the fixture to the truss as a backup in case the primary clamp fails. Safety bonds are not optional; they are a basic safety requirement for any suspended fixture.
What load can truss support?
It depends on the specific truss section, its span between support points and the total weight distribution. Manufacturers specify the load rating per metre at given spans — for example, a common 290mm box truss might support 100kg at a 6-metre span. The total weight of all fixtures, clamps, cables and accessories must be calculated and verified against the truss specification. Consulting a structural engineer or certified rigger is essential for any suspended rig.
Do I need a rigger to set up a truss lighting rig?
For any suspended installation — truss hung from ceiling beams, motors or house rigging — yes. A competent rigger is responsible for verifying load calculations, rigging point integrity and assembly safety. In many professional venues, only approved riggers are permitted to work on suspended equipment. Ground-supported truss towers that do not suspend equipment overhead can often be assembled without a rigger, but stability calculations are still required.
What is a ground support system for truss?
A ground support system uses vertical upright stands — either crank stands, tower systems or goal-post configurations — to hold the truss at height without suspending it from the ceiling. This is the standard approach for outdoor events and venues where ceiling rigging is not possible. The uprights and base plates must be rated for the horizontal truss span and total lighting load, and the base plates must be ballasted or anchored to prevent the structure from overturning.
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