EDMONTON, AB

Garth Worthington School GLT Stair Variance

The Garth Worthington School is a two-storey, 4,300 m² K-9 school in Edmonton, Alberta, made of noncombustible construction materials.

INSTITUTIONAL

In the middle of the school, a single-storey mass timber feature stair was proposed.

The feature stair was made using glue-laminated timber (GLT).

Based on an assessment of the egress design for the overall building, and with additional mitigation measures in place, it was argued that the presence of a feature stair made of GLT did not increase the risk of injury to people nor damage to the building due to fire spread beyond its point of origin compared to a strictly code-compliant stair.

This Variance, or Alternative Solution, enabled increased architectural freedom and allowed for innovative and sustainable materials to be used to a greater extent.

The proposed glulam feature stair did not meet the Alberta Building Code requirements for materials used in a noncombustible Group A, Division 2 building.

Entuitive developed a Variance Proposal, an application to the Authority Having Jurisdiction to deviate from the code, provided that the proposed design still meets the Functional and Objective Statements, on a project-specific basis.