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OBC DIVISION B · PART 3 · SECTION 3.17 — DEMOUNTABLE STAGES AND SUPPORT STRUCTURES

When does the Ontario Building Code apply to demountable event stages?

Section 3.17 applies to demountable stages and demountable support structures, temporary staging, roof grids and rigging towers erected for events, above size thresholds set in the code. Regulated structures are designated structures requiring a building permit and engineered design.

Code reference
Section 3.17 governs demountable stages and demountable support structures, the temporary platform, roof and rigging structures assembled for performances and events, above prescribed size and height thresholds. Regulated structures require a permit under the Building Code Act and must be designed, erected and reviewed in accordance with the section's structural and safety requirements.
OBC Division B, Section 3.17 (Demountable Stages and Demountable Support Structures)

Paraphrased for clarity — open this provision in the BUILDAiD Library for the exact wording.

What this means in practice

Section 3.17 is an Ontario-specific addition adopted after the 2012 Downsview Park stage collapse in Toronto, which killed a drum technician before a Radiohead concert. It ended the regulatory gap where large temporary stage roofs were treated as neither buildings nor equipment. Practically, event producers must now build permit timelines into show schedules: municipalities need engineered drawings before erection, and the structure cannot simply appear overnight. Small platform stages below the thresholds stay exempt, but touring-scale roofs, ground support towers and video walls on ballasted frames typically are regulated.

Plain language

After a Toronto concert stage collapsed and killed a crew member in 2012, Ontario wrote big temporary stages into the building code. Large event stages and their roof structures now need a building permit and an engineer, just like a building.

Related questions

What engineering is required for demountable stages and support structures in Ontario?Are guards required on the edges of temporary stages in Ontario?What inspections are required for demountable stages in Ontario?

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This page is provided for general information. Building code requirements depend on your specific project, occupancy and municipality, and code editions change. Always verify requirements against the current Ontario Building Code and confirm with your local building department.