Wire Balustrading Installation Recommendations
The Building Code of Australia Volume 2 Part 3.9.2, sets out the construction requirements when using a wire balustrade.
There are a number of combinations that can be used in terms of post spacing, wire diameter, lay and wire spacing to achieve the performance requirements of the Code relative to minimum wire tension and maximum wire deflection.
However, the following guidelines set out the minimum specifications permitted for the installation of horizontal wire balustrading using a standard configuration of members:
- A maximum post spacing of 1.8 metre;
- Wire must be stainless steel minimum 3.0mm diameter (lay of 19 wires);
- Droppers must be placed at maximum 900mm centre and secured top and bottom;
- Tensioners must be placed to each strand of wire and must be at each change of direction (30º or more is considered and change of direction);
- A solid top rail is required, for steel tubing minimum 40mm diameter, for timber as per Timber Framing Manual Supplementary Tables;
- A maximum wire spacing of 80mm;
- Wire must be tensioned to 670 newtons when measured with a strain indicator or not deflect more than 6mm when a 2kg mass is suspended mid-span between supports.
If you wish to vary from the configurations nominated in the Code, you will need to provide Engineers Computations justifying that the wire balustrading can conform with the requirements of the Building Code of Australia (Part 3.9.2) and AS1170.1 – Clause 4.7.
Note: Horizontal wire balustrade cannot be used on ‘high’ decks where the floor/balcony level is more than 4.0m above ground level.