Balconies often have very shallow slabs requiring drainage and waterproofing to be very compact. Linear drainage is often preferred to prevent four-way falls in the balcony from floor wastes.
AS 3500.3 was updated in 2018 and sets strict requirements for balconies and terraces to ensure that drainage in these areas is adequate. It calls for two drainage methods to satisfy both a 20 year storm and a 100 year storm,
This translates to a drainage channel or floor waste to capture runoff from a 20 year storm event and an additional design contingency to capture runoff from a 100 year storm event. This could be an additional drainage channel, although maintenance is critical for this ‘emergency’ drainage, a gap under a balustrade or a hole in the side wall of the balcony to evacuate water during high storm events.
Click here to learn more about ACO BalconyDrain.