What We Did and Why
Indoor mould is a visible signal of a more serious, underlying issue – excess moisture within the building envelope. Whether caused by defective cladding, leaking plumbing, or unmanaged water vapour, moisture accumulation poses a risk to human health, structural integrity, and property value.
In Victoria, water-related building defects are among the most frequently reported issues to insurers, regulators, and dispute resolution bodies. To better understand the scale and underlying causes of indoor mould and moisture damage, RIC Solutions collaborated with Victoria University and the Victorian Managed Insurance Agency (VMIA) to deliver a research-based scoping study.
The research focused on accepted domestic building insurance claims and drew on building permit data from the Victorian Building Authority (VBA). Led by Dr Tim Law of Victoria University, the study aimed to inform future inspection programs, industry education, and regulatory reform.
How We Approached It
Our investigation analysed 2,178 accepted domestic building insurance claims between July 2018 and November 2020. Of these, a staggering 92% involved at least one water-related defect. Using a metadata review and a representative sample of 54 claims, we undertook a desktop analysis of insurance inspection reports and building permit documentation to identify patterns and root causes.
The work was guided by rigorous analysis of documented defects, expert assessment of construction practices, and consideration of system-level weaknesses in design, certification, and construction.
Key Findings
The study uncovered two primary contributors to moisture ingress and mould growth:
- Poor or incomplete design documentation
- Non-compliant construction of balconies and internal wet areas
Root causes were often linked to:
- Design complexity exceeding the technical capabilities of project teams
- Failure to meet waterproofing standards due to inadequate detailing or supervision
- Insufficient awareness of construction moisture risks across disciplines
The Impact
The study provided evidence-based recommendations to reduce moisture-related building defects and support healthier homes. These included:
- Improved education for designers, surveyors, and builders on waterproofing and weatherproofing
- Mandatory inclusion of critical detailing in design documents
- Targeted inspections of high-risk elements such as balconies and wet areas
- Use of technology, including drones and digital reality capture, to support safer and more accurate inspections
- Enhanced cross-sector dialogue between health and building professionals
Insights from the research have already informed the VBA’s Proactive Inspections Program and underpinned future-focused regulatory efforts. The findings also shaped the VBA’s 2022 Research Grant Program and contributed to discussions at the 2023 Building Surveyors Conference.
Why It Matters
This study reinforces the connection between building design, construction quality, and occupant health. It demonstrates the importance of evidence-based oversight, professional education, and early intervention to prevent costly and harmful building defects.
As part of our ongoing commitment to improving built environment outcomes, RIC Solutions continues to use scientific analysis, industry collaboration, and regulatory insight to reduce compliance risk and improve the quality of homes across Australia.
