Rigging point

A rigging point is a single attachment to the structure above: a beam clamp, a shackle through a padeye, a sling round a steel member. A rig is described in points because that is the unit the building is rated in.

Purpose-built venues publish what they will take, and the numbers are specific rather than general — a given capacity per point, different in each hall, and often different from one structural member to the next within the same room. The plot has to show which member each point lands on.

Hotel ballrooms are where this gets difficult, and it is the single most useful thing a planner can know in advance. A great many ballrooms publish no rigging capacity at all, because the ceiling was not designed to be hung from. In that situation there is no defensible number to work to, and the options are a structural engineer’s assessment of the actual members, obtained through the venue, or ground support instead. Guessing from the fact that somebody hung something there last year is not an assessment.

Points are also a scheduling item. At larger venues the rigging plot has to be submitted and approved weeks ahead, the attachment work is done by the venue’s own riggers, and nothing hangs until both of those have happened.

Staging and rigging — owned inventory, our own crew, and a site survey before anything is specified.

• Point load The force delivered into one attachment — the number a building is rated against, and the reason total rig weight is the wrong thing to quote a venue.
• Rigging plot The drawing that says what hangs where, how heavy each point is and how high it trims — submitted to the venue weeks ahead, not produced on the day.
• House rigger The venue’s own rigging crew, who in most convention centres and arenas are the only people permitted to attach anything to the building — a cost and a schedule item, not an optional service.