Single exit stairway buildings could make cities denser and safer

A Toronto six‑unit apartment designed with a single shared stair was granted special approval, joining recent moves in Vancouver and other cities to revisit rules on single exit stairway buildings. The article reports that proponents point to modern sprinklers, fire‑resistant materials and research showing strong safety records for four‑ to six‑storey designs equipped with sprinklers.

A Toronto infill project by Office Ou received municipal approval to use a single shared stair rather than the two stairwells normally required by Canadian practice. The design aims to create apartments with more daylight and cross‑ventilation and a shared stair where neighbours meet. This approach is common in many countries and is now prompting Canadian cities and national code officials to reconsider long‑standing rules. Key details: - The Toronto project secured a permit through an "alternative solution" process that added sprinkler systems, enhanced fire‑resistant construction, wider stair landings and mechanical ventilation for smoke control. - Vancouver City Council recently amended local rules to allow single exit stairway apartments, and Edmonton and Toronto have published guidance or pathways for alternative solutions. - The article notes that single exit stairway designs are common in Europe, Australia and parts of Asia, where buildings of many storeys use similar layouts. - Research cited in the article (Pew Charitable Trust) found that four‑ to six‑storey single exit stairway buildings with sprinklers have a strong safety record compared with conventional apartment buildings and single‑family homes, and construction costs can be 6–13% lower. - Proponents say the layout can produce more livable family units, add modest density to low‑rise neighbourhoods and create a different social dynamic through shared circulation spaces. Summary: The reported approvals and code adjustments indicate a gradual shift in how some Canadian jurisdictions evaluate single exit stairway designs, balancing modern safety systems against older prescriptive requirements. Officials overseeing the National Building Code and several cities are adapting guidance and approval routes; whether this leads to broader code changes will unfold as more projects seek permits and offer performance data.