As a homeowner or strata manager, maintaining the integrity of your apartment building’s balconies is crucial to prevent water damage and ensure the safety of residents. In New South Wales, the Design and Building Practitioners Act (DBPA) legislation requires building owners to ensure that any re-waterproofing work meets specific standards. Here’s a step-by-step guide to help you navigate the process:
Understanding DBPA Legislation Requirements
The DBPA legislation aims to ensure that building work, including re-waterproofing, is done to a satisfactory standard. As a building owner, you’re responsible for:
- Engaging obtaining regulated designs by a Design Practitioner to ensure ensure the work meets the requirements of the Building Code of Australia (BCA) and relevant Australian Standards (AS 4654.1 and AS 4654.2).
- Engaging a Building Practitioner to carry out the works.
NSW Fair Trading provides a handbook for design practitioner which can be found here in the link here.
The legislation requires that the design practitioner provides the regulated design for the class of design. There are many class such as Structural, Facades, Architectural, Fire & Mechanical.
Balcony and roof waterproofing are required to be prepared by the following design practitioner that are registered in the following class:
- Architectural
- Facade
- Building Design.
The NSW Government has a register to verify the classes of design practitioner in the link here
Before you start re-waterproofing your balcony or roof, the following steps are recommended:
Step 1: Assessment and Planning
- Identify the source of water damage or leaks.
- Engage a professional to assess the balcony’s condition and recommend the best course of action.
- Develop a plan and budget for the re-waterproofing work.
Correctly identifying the source of the leak is critical and often overlooked. There is nothing worst than to replace an entire balcony waterproofing system to find out the leaks it related to the door or another issue.
With the correct assessment, unnecessary building works can be avoided and a practical and cost effective solutions can be provided to address the issue. Water testing can be undertaken a this stage to confirm the leaks before the works was completed so that it could be verified at the end that the work have solved the leaking issue.
Step 2: Engage a Design Practitioner
- Ensure the design practitioner has experienced in balcony and roof waterproofing.
- Verify their compliance with DBPA legislation requirements.
- Obtain the regulated designs.
The construction cost of the works depends a lot on the experience and practicableness of the Design Practitioner.
Design practitioner often suggest to rip up all the tiles and screed and start again, however it may not always be practical. Full demolition is costly and disruptive as the existing membrane is required to be grinded with loud machinery.
There are several ways that a design practitioner would work around this while meeting Australia Standards and Building Code.
Below are just several practical solutions that Excelo Consulting Engineers considers in designing your external waterproofing systems:
- Installation of sheet waterproofing membrane over the existing finish and install a pavers on pedestals system.
- This solution is works well where there is adequate vertical termination and falls in the floor.
- Installation of sheet waterproofing membrane over a torched-on waterproofing membrane.
- The additional costs of mechanically grinding out the existing membrane typically outweigh the cost for the more superior sheet membrane system.
- PVC sheet membrane supplier, Fatra offers these solutions which can be found here.
- Installation of a liquid waterproofing membrane over an existing waterproofing membrane.
- Depending on the conditions of the membrane, this solution may offer best value.
- Tremco AlphaGuard Bio is one the remedial waterproofing system suitable for this solution.
The Design Practitioner should select compliant waterproofing membranes to AS 4654.1 only. A complete list of compliant waterproofing membrane can be found in the XLOBuild Waterproofing membrane database here.
Step 3: Engage a Building Practitioner
- Engage the Building Practitioner
- Upload the regulated design to the planning portal
- Carry out the work in accordance with the regulated design
Ensure that the contractor is a registered Building Practitioner from the NSW Government link here.
If you need help looking for a remedial builder, XLOBuild provide a directory of remedial builders that can be found here.
The building practitioner should review the regulated design and liaise with the design practitioner and iron out any issues.
The regulated designs must then be uploaded into the planning portal and carry the works out accordingly.
Step 4: Testing and Inspection
- Conduct thorough testing to ensure the waterproofing system is effective.
- Inspect the work to ensure it meets DBPA legislation requirements.
The Design Practitioner should undertake the visual inspection of the waterproofing membrane and carry out necessary checks including adequacy of the following:
- Waterproofing membrane dry film thickness
- Junctions/ fillets and bondbreakers
- Extent and termination of the membrane
- Waterstops.
- Waterproofing membrane is free of voids, pinholes extrusions and contaiminates.
Step 5: Documentation and Compliance
- Obtain all necessary documentation, including warranties and certification.
- Ensure compliance with DBPA legislation requirements and relevant building codes.
Excelo Consulting Engineers provides practical and cost effective solutions. We carry out peer-reviews and value engineering to achieve desired functions at the lowest possible cost without compromising quality or performance