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OBC DIVISION B · PART 3 · SECTION 3.16 — SHELF AND RACK STORAGE SYSTEMS

How does high rack storage affect sprinkler requirements in Ontario?

High-piled and rack storage changes the fire challenge dramatically, so sprinkler systems must be designed for the storage height, commodity class and rack configuration, often requiring higher-density ceiling protection or in-rack sprinklers per NFPA 13 storage criteria.

Code reference
Where rack storage systems are installed, the building's automatic sprinkler protection must be designed for the actual storage arrangement, taking into account storage height, the commodity being stored, aisle widths and rack configuration. This is carried out through the referenced sprinkler installation standard, which prescribes design densities and, for some configurations, sprinklers within the racks themselves.
OBC Division B, Section 3.16; sprinkler design per Subsection 3.2.5 and NFPA 13

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

What this means in practice

Fire in racked storage behaves like fire in a chimney: flue spaces between pallets accelerate vertical spread and can outrun ceiling sprinklers. That is why introducing or raising racking in an existing warehouse is not a tenant fit-up detail, it can invalidate the entire sprinkler design basis. Verify commodity classification honestly (plastics are far more demanding than paper), maintain the flue spaces the design assumes, and expect in-rack sprinklers or ESFR heads for taller configurations. Insurers and the Ontario Fire Code both police storage height against the system's design.

Plain language

Stacking goods high on racks makes fires burn hotter and climb faster, so the sprinkler system must be designed for exactly how high and what you store. Changing your racking without checking the sprinklers can make them useless.

Related questions

When does warehouse racking need a building permit or engineering in Ontario?Do storage racks in Ontario need to be designed for earthquakes?What egress requirements apply around storage racks in warehouses 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.