Balustrades need to be at a minimum of 1 metre high and have an opening of no more than 125mm wide.
These regulations cover balustrades on stairways, balconies, verandahs and other surfaces between levels. They are intended to ensure that balustrades are high enough to prevent falling over the balustrade and to prevent children from falling through them.
Balustrade regulations and standards apply to all balustrades, not just the construction of new ones. The regulations are there for a reason: to protect people from danger.