Part G4 Construction in alpine areas
Introduction to this Part
This Part contains additional requirements for buildings constructed in an alpine area to address the potential for snow and ice to obstruct or delay evacuation and fire fighting or cause a hazard by falling on people.
Construction in alpine areas
Structures forming pathways in snow conditions
A building in an alpine area containing external trafficable structures forming part of the means of egress must be constructed so that those structures remain, as far as practicable, useable under snow conditions.
Control of falling ice and snow
Fire safety systems in alpine areas
Application of Part
External doors which may be subject to the build-up of snow must—
- open inwards or slide; and
- if inward opening, be marked “OPEN INWARDS” on the inside face of the door in letters not less than 75 mm high in a colour contrasting with that of the background; and
- be constructed so that the threshold is not less than 900 mm above the adjoining surface; and
- if it serves a corridor or stairway, be positioned in an alcove or recess with—
- no horizontal dimensions of the alcove or recess less than twice the width of the door; and
- the door positioned to open against a wall such that the distance from any part of its swing to the nearest point of entry of the stairway or corridor is not less than the width of the door.
- in every stairway (other than those within a sole-occupancy unit in a Class 2 or 3 building or Class 4 part of a building); and
- in every public corridor or the like leading to an exit; and
- externally above every doorway opening to a road or open space; and
- in any storey of the building if illumination sufficient for safe egress will not be available under conditions of emergency.
External trafficable structures
External stairways, ramps, access bridges or other trafficable structures serving the building must—
- have a floor surface that consists of expanded mesh if it is used as a means of egress; and
- have any required barrier designed so that its sides are not less than 75% open; and
- for a stairway, have goings (G), risers (R) and slope relationship quantity (2R + G) in accordance with—
- for a ramp serving as an exit and not serving as an accessible ramp, have a gradient not steeper than 1:12; and
- where a ramp is also serving as an accessible ramp under Part D4, be in accordance with AS 1428.1.
|Riser (R)||Going (G)||Slope relationship (2R + G)|
Dimensions are in mm.
Clear space around buildings
A building must be so constructed that—
- if any part of an external wall is more than 3.6 m above the natural ground level — the distance of that part from a boundary other than a road alignment is not less than 2.5 m plus an additional 100 mm for each 300 mm or part thereof by which that part of the wall exceeds a height of 3.6 m; and
- if an exit doorway discharges into a court between wings of a building and that area may be used for vehicle access to the building, the distance between wings must be not less than 4 m; and
- where an exit doorway discharges opposite a feature that could entrap snow or an embankment that is more than 900 mm above the threshold of the doorway, a distance of not less than 4 m must be provided between the doorway and the feature.
Fire-fighting services and equipment
- a manually operated fire alarm system with call-points complying with AS 1670.1; and
- fire hydrants installed in accordance with E1D2(2); and
- fire hose reels installed in accordance with E1D3(2) to (7), except that in a Class 2 or 3 building—
- for the purpose of E1D3(2), a sole-occupancy unit is considered to be a fire compartment; and
- for the purpose of E1D3(3)(b), a sole-occupancy unit may be served by a single fire hose reel located at the level of egress from that sole-occupancy unit; and
- for the purpose of E1D3(6), a fire hose may pass through a doorway in bounding construction referred to in C4D12.
Every Class 2, 3 or 9 building must display a notice clearly marked “FIRE ORDERS” in suitable locations near the main entrance and on each storey, explaining—
- the method of operation of the fire alarm system and the location of all call-points; and
- the location and methods of operation of all fire-fighting equipment; and
- the location of all exits; and
- the procedure for evacuation of the building.