Handrails and balustrades
Handrails and balustrades are an important safety consideration.
When balustrades or handrails are required
Balustrade or handrails must be provided along the side of any stairway or ramp, any floor, corridor, hallway, balcony, verandah, or the like, and along the side of any path to a building if it is not bounded by a wall and the surface level beneath is more than one metre away.
This requirement also applies to a bedroom window opening if the opening is two metres or more above the surface level below.
Construction of balustrades or handrails
Balustrade or other barrier must be installed in accordance with the following:
- The height must not be less than:
a) 1 m above the floor of any access path, balcony, landing or the like; or
b) 865 mm above the nosing of the stair treads or the floor of a ramp
- A transition zone may be incorporated where the balustrade or other barrier height changes from 865mm on the stair flight or ramp to one metre at the landing.
Openings in balustrades
Openings in balustrades (including decorative balustrades) or other barriers must be constructed so that any opening does not permit a 125mm sphere to pass through it and for stairs, the space is tested above the nosing line.
Finished floor level
Where the finished floor level is more than four metres above the surface beneath, any horizontal elements within the balustrade or other barrier between 150 mm and 760 mm above the floor must not facilitate climbing.
For this purpose, a wire balustrade consists of a series of tensioned wire rope connected to either vertical or horizontal supports. A wire balustrade excludes wire mesh fences and the like.
Where wire balustrade is proposed to be used, it must be constructed in accordance with Clause 22.214.171.124 of Volume 2 of the Building Code of Australia.
The handrails and balustrading information sheet contains post spacing, wire spacing and wire types, tension and deflection requirements for vertical and horizontal wire balustrades systems. The figures contained in the information sheet are an extract from the Building Code of Australia and were derived from testing the spacing combinations in order to prevent the passage of a 125 mm diameter solid cone penetrating between the wires at a predetermined force.
Care needs to be taken to ensure that wire tension will be maintained during the life of the balustrade. In some situations, it may be necessary to incorporate "lock-off" devices to prevent loosening of the wire. Likewise, if a threaded anchor bears against a soft wood post or rail, the anchor may indent the post or rail, thus loosening the wire.
Temperature effects on the tension of the wire may be significant but there is little that can be done to allow for temperature variation in service. The shorter the wire span, the lesser the effect will be.