Blue Eco Homes submission to the NSW Portfolio Committee No. 2 – Health Inquiry on Clean Indoor Air
About Blue Eco Homes
Blue Eco Homes is a NSW based building practice specialising in sustainable, high-performance buildings, including Passivhaus-certified homes and public-facing facilities. Our work focuses on delivering verified indoor environmental quality outcomes through fabric-first design, airtight construction and balanced mechanical ventilation.
This submission is informed not only by our building experience, but also by lived and professional health expertise. Merylese Mercieca, co-owner of Blue Eco Homes, has a background in respiratory health and brings a health-first lens to building design, particularly for people with asthma, allergies, compromised immunity and chronic respiratory conditions.
This construction and respiratory health dual perspective is supported by NSW-based indoor air quality monitoring and documented respiratory health outcomes published in a 2024 case study authored by Blue Eco Homes.
More on our work and evidence-based approach is available at https://blueecohomes.com.au
Introduction
Indoor air quality (IAQ) is a public health, housing and equity issue that sits across health, education, work health and safety and building regulation. Poor IAQ contributes to preventable illness, reduced learning outcomes, workplace risk and increased strain on health services. These impacts are magnified in schools, healthcare facilities and social housing, where occupants often have limited ability to modify their environment or avoid exposure.
From a building perspective, IAQ outcomes are largely determined by design decisions that are well understood and achievable: airtightness, moisture control, adequate ventilation and effective filtration. The challenge in NSW is not a lack of knowledge, but inconsistent implementation, limited monitoring and insufficient focus on performance verification.
This submission draws on NSW-based monitoring and health outcome data comparing a code-compliant apartment and a certified Passivhaus dwelling, which demonstrated substantial reductions in indoor pollutants and corresponding improvements in respiratory health within weeks of occupancy.
(a) Impacts of Poor Indoor Air Quality
(i) Health
Poor IAQ is strongly associated with respiratory irritation, asthma exacerbation, allergic disease, headaches, fatigue and increased transmission of airborne pathogens. In social housing, where residents may already experience higher rates of chronic illness and overcrowding, poor ventilation and moisture control can entrench health disadvantage and increase reliance on acute health services.
Children, older people and those with pre-existing respiratory conditions are particularly vulnerable. From a respiratory health perspective, prevention through clean indoor air is one of the most effective and least invasive interventions available.
NSW-based monitoring has demonstrated that improved ventilation, airtightness and humidity control can deliver rapid respiratory health benefits. In one documented case, a resident with chronic respiratory symptoms experienced significant reductions in asthma symptoms, fatigue and medication reliance within weeks of moving from a code-compliant apartment to a high-performance home, alongside measured reductions in carbon dioxide, particulate matter, volatile organic compounds and mould exposure.
The health impacts of poor indoor air quality disproportionately affect people living with chronic health conditions, many of whom are already advised to avoid infection and environmental triggers. Given that approximately half of the population lives with at least one chronic condition, improving indoor air quality should be understood as a mainstream, population-level preventative health measure rather than a niche intervention.
(ii) Productivity and Economic Output
Poor IAQ reduces cognitive performance, concentration and decision-making. In schools, this directly affects learning outcomes. In workplaces and public service buildings, it contributes to absenteeism, presenteeism and reduced productivity.
In social housing, the economic impacts are indirect but significant: increased healthcare utilisation, reduced ability to work or study and higher long-term public expenditure.
Measured indoor air quality data indicates that elevated overnight carbon dioxide and pollutant levels are common in code-compliant dwellings and are associated with poor sleep quality, fatigue and reduced daytime functioning. Improved ventilation and filtration have been shown to restore healthy sleep patterns and cognitive alertness within a short timeframe, with flow-on benefits for learning, work participation and service continuity.
(iii) Work Health and Safety
Ventilation is a recognised engineering control under WHS frameworks. Inadequate ventilation increases exposure to airborne contaminants and infectious aerosols, creating avoidable workplace risk for teachers, healthcare workers, carers and public servants.
This risk is often highest in older public buildings and social housing maintenance environments, where systems are ageing, poorly commissioned or under-maintained.
(iv) Equity of Access to Public Services and Spaces
Equity requires that all people can safely access education, healthcare and housing. Poor IAQ undermines this by disproportionately affecting those with the least choice such as residents of social housing, students in older school buildings and patients in overstretched health and aged care facilities.
Emerging accessibility and respiratory health guidance recognises indoor air quality as an often overlooked but critical accessibility issue. For people living with chronic respiratory, immune and cardiovascular conditions, unsafe indoor air functions as an invisible barrier, limiting safe access to schools, healthcare facilities, workplaces and other public services in the same way that physical barriers restrict access for people with mobility impairments.
Recognising indoor air quality as a matter of accessibility reframes clean air as a shared responsibility, rather than placing the burden of risk management on individuals who are already vulnerable.
Evidence from our NSW-based case study indicates that occupants of code-compliant buildings may still be exposed to elevated mould, nitrogen dioxide and fine particulates due to design limitations rather than misuse or poor maintenance. This reinforces the need to address indoor air quality at the building system level, particularly in social housing where residents have limited agency to mitigate exposure.
Clean indoor air should be considered a baseline service, equivalent to thermal comfort and water quality, not a premium feature.
(b) Indoor Air Quality Standards and Monitoring
While the NCC and associated guidance recognise ventilation and IAQ, there remains a gap between intent and real-world performance, particularly in public buildings and social housing.
Key issues
• Limited mandatory monitoring of IAQ once buildings are occupied
• Reliance on design assumptions rather than measured outcomes
• Inconsistent maintenance and verification of ventilation systems
Minimum monitoring framework for public buildings and social housing
• CO₂ (ventilation adequacy proxy)
• PM2.5 (particulates and smoke exposure)
• Relative humidity (mould and condensation risk)
• Temperature (thermal stress interaction)
NSW-based monitoring demonstrates that these parameters are not theoretical. Carbon dioxide levels exceeding 4000 ppm, particulate matter above WHO guidelines, nitrogen dioxide associated with gas appliances and humidity above 65% were all recorded in a code-compliant apartment.
Routine monitoring makes invisible risks visible and supports timely intervention.
However, monitoring alone is insufficient without clear guidance and education for developers, builders, asset owners and occupants on how to interpret IAQ data and respond when levels fall outside recommended ranges. Without this shared understanding, monitoring risks becoming a passive reporting exercise rather than an active health protection tool.
(c) Solutions to Improve Indoor Air Quality
(i) Building Design — Schools, Health Services, Social Housing and Public Buildings
High-performing IAQ outcomes are achieved through:
• Fabric-first design to reduce uncontrolled air leakage
• Balanced mechanical ventilation delivering filtered outdoor air
• Moisture management to prevent mould growth
• Low-emissions materials to reduce chemical load
• Commissioning and verification to confirm systems work as intended
In social housing, these measures are particularly important because occupants often cannot modify behaviour or install supplementary systems themselves.
Passivhaus provides a proven performance framework that verifies airtightness and ventilation outcomes, rather than assuming compliance.
Comparative monitoring has shown that buildings designed around airtightness, balanced mechanical ventilation and moisture control can reduce key indoor pollutants by 75–95% compared to standard construction, while maintaining stable temperature and humidity within recognised health ranges. Importantly, these outcomes were achieved without reliance on occupant behaviour.
Where monitoring is provided, clear education is also required so building owners, facility managers and occupants understand what the data means, what constitutes normal or concerning conditions and what actions should be taken if thresholds are exceeded. This is particularly important in social housing and public buildings, where occupants may have limited ability or authority to respond independently.
(ii) Retrofit Measures and Emerging Technologies
Given the age of much NSW public and social housing stock, retrofit is essential.
Priority retrofit measures
• IAQ monitoring deployment in all high-occupancy public and social housing buildings
• Ventilation system tuning and increased outdoor air rates
• Filter upgrades and portable HEPA filtration where systems are constrained
• Condensation and moisture risk remediation
Staged upgrades allow meaningful health improvements without full rebuilds.
(d) Climate Resilience and Pandemic Preparedness
IAQ is central to NSW’s ability to respond to climate and health shocks.
• Bushfire smoke: filtration and controlled ventilation protect residents and enable buildings to remain habitable
• Heatwaves: airtight, well-ventilated buildings provide safer indoor refuge
• Pandemics: verified ventilation reduces airborne transmission risk
Buildings that consistently maintain low particulate levels through controlled ventilation and filtration are better positioned to protect occupants during smoke events and periods of poor outdoor air quality. Evidence from high-performance dwellings shows that indoor particulate concentrations can be kept well below health thresholds even when external conditions are variable.
From an equity and resilience perspective, improved indoor air quality reduces the need for vulnerable individuals to self-exclude from public spaces during smoke events, heatwaves or periods of heightened infectious disease transmission. Buildings that can maintain safe indoor air during these events support continuity of education, healthcare delivery and social participation, particularly for residents of social housing who are least able to relocate or modify their indoor environments.
(e) Other Related Matters
Verification and Accountability
Performance-based outcomes must be verified, not assumed. Public buildings and social housing funded by taxpayers should demonstrate measured IAQ outcomes over time.
Maintenance and Capability
Ventilation systems require ongoing maintenance. Clear responsibility, funding and training for asset managers are essential to avoid health risks re-emerging after initial upgrades.
Capability building should extend beyond technical maintenance to include education for those responsible for operating and occupying buildings. Clear, consistent guidance is needed so IAQ monitoring results are understood, acted upon appropriately and escalated when necessary, ensuring health protections are maintained over time rather than eroding after initial upgrades.
Conclusion
Indoor air quality is a solvable problem with clear health, economic and equity benefits. NSW has an opportunity to lead nationally by embedding measurable IAQ standards, prioritising schools, healthcare and social housing, funding targeted retrofits and requiring verification of real-world performance.
NSW-based evidence demonstrates that improved indoor air quality is not theoretical or aspirational. It is measurable, achievable within current construction capability and delivers rapid health benefits. These findings support the inclusion of performance-based IAQ standards and verification pathways in future policy and investment decisions.
Clean indoor air should be treated as essential public infrastructure.
Contact
Blue Eco Homes
https://blueecohomes.com.au
Reference
Blue Eco Homes White Paper – Passivhaus and Health
https://blueecohomes.com.au/resources
