National baseline
Start with the NBC provisions governing occupiable roofs, guards, structural loads, and egress before narrowing to the specific rooftop condition.
Canadian building code question
Rooftop decks and patios are subject to guard requirements, structural live load provisions, egress path considerations, fire separation between the roof and occupied spaces below, and accessibility obligations. The exact requirements depend on the occupancy, whether the rooftop is an occupiable space or an assembly area, and how the province has adopted the applicable provisions.
Rooftop occupancy is increasingly common in commercial and residential projects, but the code requirements extend well beyond adding furniture on a roof. The classification of the rooftop space — whether it is an amenity area, assembly space, or simple occupiable terrace — drives which guard heights, structural loads, egress paths, and fire separation provisions apply. The safest first step is to classify the intended rooftop use before checking each provision.
Start with the NBC provisions governing occupiable roofs, guards, structural loads, and egress before narrowing to the specific rooftop condition.
Confirm how the province adopts the rooftop occupancy provisions and whether any amendments change guard heights, load requirements, or egress obligations.
Assembly-type rooftop uses can trigger higher guard loads, different occupant load calculations, and additional fire safety requirements compared to a simple amenity terrace.
The required guard height depends on how the rooftop is classified and used. Assembly-type rooftops, residential amenity areas, and restricted-access roofs can have different guard height requirements.
If the rooftop is an occupiable space and the building is required to be barrier-free, then accessibility provisions typically apply. The requirement depends on the building's overall accessibility obligations.
The structural assessment depends on the original design loads and the intended rooftop use. Occupied rooftop spaces typically require higher live loads than a standard roof condition.