BCA-07

Number of Exits Required in a Class 2 Building BCA: Clause D1.2

AUST  Hendry building surveying consultants advise that the Building Code of Australia in Part D1 ‘Provision for Escape’ contains clause D1.2 ‘Number of exits required’. This article provides designers with an example of exit requirements for a Class 2 building.

/ BUILDING CODE OF AUSTRALIA: CLAUSE D1.2 – ISSUE
Various requirements apply to exits in a Class 2 building with a basement carpark.

/ BUILDING CODE OF AUSTRALIA: CLAUSE D1.2 – EXPLANATION
The following illustration explains the requirements for exit arrangement in a Class 2 building.

Depicted is a basement carpark requiring two exits opening onto the street, which are provided by stair 2 and the exit door. The ground floor also requires two exits (minimum) but stair 2 cannot be used so the exit door B and door A are required as exits. Stair 1 can be used as an exit to the carpark as it will discharge 15m from an exit doorway at ground level, however the front entrance door B is more appropriate.

For egress, the first floor only needs a single stairway as unit entrance occurs within 6m of the stair. Stair 3 on the ground floor must discharge within 15m of door A. The corridor requires compartmentation by a smoke door so that the corridor is limited to a 40m length and to smoke separate the exits.

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