Over the last year or so, waterproofing awareness has become a hot topic within Australia.
The focus on waterproofing practices within the Australian construction industry has intensified due the unfortunate cladding crisis, which in turn uncovered serious waterproofing defects.
Alongside, or because of, these recent developments the Australian Institute of Waterproofing (A.I.W) has gained momentum by being part of meaningful discussions with the Master Builders Association (MBA), Housing Industry Association (HIA), Victorian Building Authority (VBA), and Standards Australia.
It is unfortunate that it had to be due to significant failures that led to these collaborations, however at long last the A.I.W has gained access to industry stakeholders. Even though it has been an exceptionally long road to creating awareness about waterproofing in construction, I cannot be more pleased with the direction of these discussions.
Unfortunately, and it was not that long-ago waterproofing was completely overlooked during the critical stage of design and specification, mostly noted on drawings simply as: “waterproofing as required” or similar. Consequently, onsite construction personnel gave little respect to waterproofing, often leading to the failures we witness all too often today.
Onsite practices would typically involve the builder with a last-minute conversation along the lines of:
Builder: Mate can you swing by and do some waterproofing on my job.
Contractor: Ok how much area, when and what do you want?
Builder: Drawings and specification indicate, “waterproofing as required”, so provide whatever is quickest and cheapest and as waterproofing not in the schedule, no time or costings have been allowed. And whatever you use, I need a warranty and waterproofing certificate, or my Building Surveyor won’t pass my job.
The above scenario reflects the worse of waterproofing in Australian construction:
- Waterproofing given little consideration in design, specification, or onsite.
- Waterproofing often failed to be costed within the build or if so, maybe a random stab in the dark figure. Lack of planning means cost cutting on product/s, application, and installation is imperative.
- Substrate preparation for waterproofing is time consuming but is a vital stage to achieve membrane longevity. Time constraints rarely takes this into consideration.
- Little appreciation of how weather affects external waterproofing – it must be done now. Surface temperature and moisture content at time of application affects all waterproofing membranes. The optimum substrate being clean, dry, and neither too hot nor too humid.
- “Respect” of newly installed waterproofing membranes on construction sites is dismal: frequent damage from careless work practices due to ladders and tools of trade etc. Trades coming in and working over a newly installed membrane have scant regard. Many membrane failures and water leaks can be attributed to onsite trades.
The A.I.W continues to educate, share knowledge, and gain better work practices for waterproofing.
An important focus for the A.I.W is waterproofing for basements, foundations and below grade tanking. Currently there is no Australian Standard for Below Ground Waterproofing. The National Construction Code (NCC or ABC) has no reference for “Below Ground Waterproofing” and thus no set compliance solution or Australian Standard.
With the growing trend of residential and commercial buildings utilising below ground space for parking and designs with “habitable rooms” in basements, these builds rely on compliance requirements that demand only a “Deemed-To-Satisfy” standard.
Consequently, the Australian Institute of Waterproofing is working hard to create an “Australian Guide to Below Ground Waterproofing”. The A.I.W is referencing the British Standard – BS 8102:2009, as this is considered by experts in the waterproofing industry as being the most transferrable to create Australia standards. Several A.I.W Committee members travelled to the UK last year to attend training and certification in the British Below Ground Stand BS8102.
The Australian Below Ground Standard would require either a dry basement which involves sealing the entire under floor slab and walls ( usually behind shotcrete or masonry walls) where the wall and underfloor waterproofing membranes tie together to form a water tight envelope; or a controlled water runoff system which allows water to flow behind the walls of the habitable room into a sump pit and then pumped out, thus keeping the habitable area dry. In certain circumstances a combination of the above waterproofing practices maybe applicable.
The A.I.W Technical Team (please note the AIW committee members are all volunteers) is working hard to adapt the British Standard – BS 8102:2009 into an “Australian Guide to Below Ground Waterproofing”.
The aim is a practical reference for everyday use. The “Guide” to be in plain language and workable for all construction professionals: those at the design and specification stage, the builder taking responsibility to construct watertight areas and for the waterproofing contractor at the point of membrane installation.
As President of the A.I.W, I have been in discussions with Australian Standards and am anticipating an outcome to our efforts so that Australia will eventually have standards for Below Ground Waterproofing.
AIW Committee members are also on the current Standards Revision Group for the AS 3740 (above ground) Domestic Wet Area Standard, recommending amendments and clarifications. The Australian Tiling Standards Committee for BD-044 which focuses on the fixing of tile and stone etc is being Chaired by one of our AIW Committee Members.
Prior to Covid-19 restrictions, the A.I.W were active participators at seminars and conferences across Australia highlighting the critical importance of waterproofing in construction. Having face-to-face meetings provided the AIW with immediate feedback and overwhelming many stakeholders within the construction industry are as concerned as we are about waterproofing defects, standards, and training.
In Australia we have reached across the country in most states presenting to construction professionals on standards, design, correct methodology and share unfortunate water disaster cases (of which there is plenty) to grab attention. At the start of 2020, I attended the Safe Buildings and Defects Management Summit in Brisbane and opened a “lively” discussion on cladding and waterproofing defects. And then in Melbourne the A.I.W was well represented at the “Building Defects Crisis – Not Just a Sydney problem” involving construction lawyers, façade engineers and Membrane Industry Representatives.
Other AIW members are active in running webinars on various problematic topic such as correct installation of membranes, water stops in domestic bathrooms and wet areas.
I have represented the A.I.W at International conferences seeking out opinions and discussions and had the opportunity to present at the Waterproofing Membranes International Conference (Cologne Germany), tackling the rather large topic “Waterproofing Challenges in Australia’s Construction Boom”. As A.I.W President I was also an invited speaker to Shanghai China’s International Waterproofing Forum and presented on the “Challenges of Waterproofing Design and Application”.
Waterproofing awareness in Australia is now higher than ever.
I consider the A.I.W have played a large part in gaining this recognition and am immensely proud of the dedication, expertise, and knowledge by our committee and members. Collectively our aim is to provide safe, secure, and watertight buildings in Australia.
Let us continue and build even further awareness of waterproofing in construction.
Article by Paul Evans
President – Australian Institute of Waterproofing (AIW)
Managing/Director - Findlay & Evans Waterproofing
Telephone: (03) 8812 2918
Registered Victorian Building Practitioner (RBP) – Building Practitioners Board License DB-U 7983
Master Builders Association Victoria (MBAV) Specialist Contractor – License 09450
Australian Institute of Waterproofing (AIW)
Address: 155 Barkly Ave Burnley Vic 3121
PH: 1300 249 466