Australian External Waterproofing Standards Amongst the Best in the World
Houston You Have a Problem!
by John Rathbone, current member of BD-13 Committee working on Australian Standards for Waterproofing
Well to be honest it’s not Houston, it’s a deck in Canada but balconies in all developed countries that have problems like the ones shown in the above photo, that was spotted by a Wet-sealer on holiday (we never sleep), for example no fall to outlets and no membrane covering the deck plus the post penetrations are not sealed. My point is that there still seems to be many people in our own industry that are not aware that Australia doesn’t only have a Standard for Balconies but that it is now referenced in the BCA and that it has procedures to deal with every day problems. Please note: If the Australian Standard is compared to External Waterproofing Standards in other countries it is seen to be superior due to the following:
- It deals with problems that are encountered every day on roofs and balconies – European and American Standards assume that upstands will be sufficient and have no procedures for membranes below the door sills and the essential waterstop behind the door.
- It is set out so that the procedures and requirements for each section are complete – one of the best External Waterproofing Standards from another country fails on this count as it contained too many detailed procedures interspersed with comments so that Builders and Certifiers have had difficulty complying with this Standard.
- “Recurring problems are fully covered” – for example sealing of post penetrations which have been fitted after the waterproof membrane has been installed and the requirement for movement joints in tile installations, the lack of which has caused problems for many years.
- waterproofing of planter boxes and satisfactory methods of drainage of boxes are shown.
- a suitable method for waterproofing sliding door sills where the deck or balcony is required to be level entry – this style of balcony is becoming more and more popular, the ageing population being a significant driver of this change.
- the requirement that all membranes must be tested (see AS 4654-1)
- overflow pipes/outlet must be the same diameter as other drainage pipes used on deck and tiled finish must not restrict the design flow of the outlet