For five Irish students and one Irish American, the date of June 16, 2015, should have been one in which they celebrated a 21st birthday party at an apartment in Berkeley, California.

Each of the six died, however, following the collapse of a balcony on the fifth floor where they were standing. Several others were injured.

Grief for families turned to outrage, however, when the California State Licensing Board subsequently ruled that the collapse had been caused by shoddy material selection and poor waterproofing workmanship, which had enabled dry rot and decay to set in within timber joists.

California is not the only state to experience problems. In New Zealand, a ‘leaky homes debacle’ saw tens of thousands of homes constructed which did not meet required watertightness standards. In 2012, a University of New South Wales study found that 85 percent of all strata units had defects – internal water leaks, cracks and water seeping in from outside of the building were the most common issues. Leaks have also been experienced in the ACT, where placement of balcony floors at the same level of internal floors has seen water enter apartments. Last year, The Age reported many of those who manage multi-storey buildings in Melbourne as saying that ‘if it has a balcony, it will leak’”.

“A leaky building syndrome is unfolding in Australia”, construction lawyer Kim Lovegrove wrote.

This matters. As shown above, poor waterproofing on timbre structured balconies can lead to rotting wood and structural collapse. Structural instability and collapse can also happen in concrete balconies where water ingress which impacts the steel reinforcing bar causes rust which swells and pushes concrete away from the bar. Shower leaks from inadequate plumbing and/or waterproofing can cause mold spores within unseen cavities (i.e walls and subfloor and tile sealants), which can lead to sickness when they enter ventilation systems.

All this raises questions about how Australian standards and practices compare internationally and how we can improve.

According to Paul Evans, President of the Australian Institute of Waterproofing (AIW) and Managing Director of Findlay & Evans Waterproofing, we are lagging. Compared with Aussies, Americans are more professional in their approach toward projects and the design criteria from a waterproofing standpoint and are more committed to getting the job done right. The UK has a detailed standard for below ground waterproofing which is tied to insurance policies and qualification and licensing requirements; Australia has no below ground waterproofing standard. Throughout Europe and America, people are prepared to pay for adequate waterproofing treatments; in Australia, it is all but forgotten.

Evans says problems stem from several areas.

Amongst many architects, designers and building surveyors, understanding of waterproofing is poor. This places responsibility for ensuring work is done correctly almost entirely onto the building contractor.

Unlike in Queensland, licensing of those conducting licensing work in Victoria is non-existent – as are trade licensing requirements generally outside of plumbing and electrical. This means anyone can undertake waterproofing work irrespective of their level of skill, knowledge or expertise.

As mentioned above, Australia unlike the United Kingdom has no below ground standard for waterproofing. As a result, there is no standardised way to address below ground waterproofing issues.

Fourth, beyond the prevention of water ingress, Evans says little if any thought is given toward control and drainage of any water which has been repelled.

Finally, the Australian construction industry remains largely ignorant of poor waterproofing repercussions and therefore adopts a blaze approach toward this area. Often, Evans said, waterproofing is not even nominated in specifications with which builders are presented during tender processes.

“There are people doing it who don’t know what they are doing and there are other people doing it who think they know what they are doing but they don’t,” Evans said, speaking about the lack of qualification requirements in Victoria.

“What we are seeing is improper materials being used and improper practices in installing those materials.”

“When they fail, the subsequent result is ginormous.”

Going forward, Evans says AIW is working on a below ground standard, which it will share among its members once complete. To improve waterproofing education, the AIW and Master Builders Association of Victoria have created a new waterproofing course. Encouragingly, mid-tier builders were increasingly asking questions about waterproofing and the materials which need to be used.

Throughout Australia, the importance of waterproofing should not be underestimated.

With effort in the right areas, prevention of water ingress in buildings can be improved.