Part 12.2 Construction in alpine areas
12.2.1
Application
New for 2022
Explanatory information
Buildings constructed in alpine areas need special consideration because of sub-zero temperatures which can create elements which restrict free movement to and from the building. The additional measures in this Part include—
- having external doorways open in a way that is not impeded by snow and ice outside; and
- for external trafficable structures forming part of the means of egress, being constructed so that they remain useable under snow conditions, and
- minimising the impact of snow build up between and around buildings.
Part 2.2 (structural provisions) and Section 13 (energy efficiency) also contain specific additional requirements for a building located in an alpine area.
12.2.2
External doors
2019: 3.10.4.2
External doors that may be subject to a build-up of snow must—
- open inwards or slide; and
- be constructed so that the threshold is not less than 900 mm above the adjoining surface; and
- in a Class 1b building, be marked “OPEN INWARDS” on the inside face of the door in letters not less than 75 mm high and in a colour contrasting with that of the background.
12.2.3
External trafficable structures
2019: 3.10.4.3
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
- any required barrier designed so that its sides are not less than 75% open; and
- for a stairway, goings (G), risers (R) and slope relationship quantity (2R + G) in accordance with—
- Table 11.2.2a; or
- Table 12.2.3; and
- for a ramp serving an external doorway, a gradient not steeper than 1:12.
12.2.4
Clear spaces around buildings
2019: 3.10.4.4]
A building must be constructed so that—
- for any external walls more than 3.6 m above the natural ground level, the distance of that part of the building from the allotment boundary (other than a road alignment) must be not less than 2.5 m plus an additional 100 mm for each 300 mm or part by which that part of the external wall exceeds a height of 3.6 m (see Figure 12.2.4a); and
- if an external doorway discharges into a court between wings of a building and that area may be used for vehicle access to the building, the clear distance between wings must be not less than 4 m (see Figure 12.2.4b); and
- where an external doorway discharges opposite a feature that could trap snow or an embankment that is more than 900 mm above the threshold of that doorway, a minimum clear distance of not less than 4 m must be provided between the door and the feature (see Figure 12.2.4c and Figure 12.2.4d).
Explanatory information: Snow build-up around buildings
The design and construction of a building in an alpine area must not aid dangerous levels of snow build-up between and around buildings. This control—
- assists with egress in an emergency; and
- helps vehicle access around the buildings, both for snow clearing and emergency situations; and
- minimises the risk of snow or ice falling from the roof onto adjoining lots or egress routes.
Explanatory information: Set-back distances
12.2.4(a) prescribes set-back requirements for external walls from the boundary of adjoining allotments. The aim is to ensure that a reasonable distance is created between buildings to reduce the amount of snow build-up between properties. 12.2.4(a) applies only to the area adjacent to that part of the wall that is more than 3.6 m in height.
Explanatory information: Distance between wings of buildings
12.2.4(b) prescribes a minimum distance between wings of a building or attached buildings where external doorways may discharge into this area. This requirement only applies where the court or wings are able to be accessed by vehicles.
Explanatory information: Embankments adjoining buildings
12.2.4(c) applies where features adjacent to an external doorway could trap snow and complicate access and egress to and from the building.