Wire Balustrade Regulations Help

What are the NCC Wire Balustrade Regulations?

Wire Balustrade Regulations in Australia are regulated under the National Construction Code (NCC) which is administered by the Australian Building Codes Board (ABCB).

The ABCB is a joint initiative of the commonwealth, state and territory governments and is applicable Australia wide. The current version of the NCC was issued in 2019 with the next version to be issued in 2022.

The NCC is issued in 3 Volumes. Volume 1 largely applies to Class 2 to 9 commercial buildings. Volume 2 largely applies to Class 1 and 10 residential buildings. Volume 3 is the plumbing code and is not applicable to the information below. The information below is derived from Volume 2 but is also applicable to volume 1.

Wire Balustrade - See references

Volume 1 - See Part 2.16 from page 145.
Volume 2 - See Part 3.9.2 from page 318.

NCC Regulations for Wire Balustrade

Wire balustrade regulations in Australia have remained essentially the same since 2005. With a basic understanding and consideration of the regulations prior to starting your wire balustrade will help ensure compliance with NCC Regulations.

Below is intended as a basic guide to the NCC Wire balustrade regulations based on AWR Solutions extensive experience in supplying wire balustrade in Australia for over 20 years. Our friendly sales team are always here to help if you have any further questions, simply email us at sales@awrsolutions.com.au or call us on 1300 781 266.

You can download a free copy of the current NCC Regulations here.

Horizontal Wire Balustrades – Most Common Situations

My Deck/ Landing height is less than 1 metre to the ground below
If your deck/ landing height is less than 1 metre to the ground below it is optional whether you have a balustrade on your deck or landing. If you choose to have a balustrade and add horizontal wires there are no requirements on how many wires you should have.

My Deck/ Landing height is more than 1 metre from the ground below
If your deck/ landing height is more than 1 metre to the ground below you will need to comply with NCC Regulations.

When can I use Horizontal Wires on my balustrade? Horizontal wires can be used on balustrades where the deck/ landing height to the area below is between 1 to 4 metres. When the deck/ landing height is more than 4 metres you will need to run your wires vertically (see below for further information)

What Height does my Wire Balustrade Handrail need to be?

The height of your handrail will need to be a minimum of 1000mm (1 metre) from your deck/ landing height to the top of your handrail. The most common handrail thickness is 40mm making the height of the handrail 960mm from the deck to the underside of the handrail.

What wire size and construction should I use on my Wire Balustrade?

Almost all wire balustrades in Australia are constructed using 3.2mm wire rope (Listed as 3.0mm in the NCC Regulations). As per the regulations you can use either 1x19 or 7x7 construction when using 3.2mm wire rope. When installing Factory swaged systems we recommend using 1x19 wire rope. When installing DIY Hand swaged systems we recommend using 7x7 wire rope.

What post and wire spacing should I have in my Wire Balustrade?

In our extensive experience we have found that having a maximum wire spacing of 80mm with a gap of 1200mm - 1500mm between support posts works best in satisfying NCC regulations. The NCC regulations allow for wider spacing between wires and posts however in our experience the tension required is unachievable or will put excessive pressure on your posts. A typical setup as decribed above with a 1000mm handrail (960mm to the underside), 80mm spacing between wires and post specing of up to 1500mm will have 11 runs of wire.

A Typical Wire Balustrade Setup

How much tension should I put on my wires?

The NCC regulations specify how much tension is required on your wires based on your wire spacing and distance between posts. See Table 3.9.2.1 below. Tension requirements are given in the table for 60mm, 80mm, and 100mm wire spacing at posts spacing gaps between 600mm and 2500mm. Wire tension can be measured using a tension gauge.

Alternatively, the NCC regulations provide a deflection table which specifies how much deflection you can have per wire when a 2 kg mas (weight) is suspended at mid span. The table specifies permissible deflection at set wire and post spacings. Note that all deflection measurements are in mm. See Table 3.9.2.3 below

 



Vertical Wires - When to use

Vertical wires can be used at any deck/ landing height and must be used in situations where the deck/ landing height is above 4 metres. The NCC regulations allow for 2 methods of constructing vertical wire balustrades; non-continuous vertical wires and continuous vertical/ near vertical wires.

Non-continuous vertical wires

The NCC regulations allow for non-continuous vertical wires i.e. Individually tensioned wires between rails. In this situation the tension required must be in accordance with table 3.9.2.1 or the maximum deflection must be in accordance with table 3.9.2.3.

Continuous Vertical/ Near Vertical Wires

In this situation wires must be a maximum of 2.5mm and be in a 7x7 or a 7x19 construction. The maximum space between rails allowed is 900mm with tension requirements specified for 80mm, 100mm, and 110mm wire spacing and must in accordance with table 3.9.2.2 shown below. Continuous vertical/ near vertical balustrade wires must pass around a pulley block with each change of direction at the support rails. The pulley block must not cause permanent deformation to the wire.  Vertical wires must have 2 pulley blocks per 180 degree change in direction. Near vertical wires may only require 1 pulley block per change in direction.


For further advice or help with the wire balustrade regulations please feel free to email us at sales@awrsolutions.com.au or call us on 1300 781 266.