If We Spend 90% of Our Lives Indoors, Why Aren’t We Talking More About Indoor Air Quality?

Indoor air quality in homes is becoming an increasingly important issue as Australians spend more time indoors.

We recently read an ABC article about the growing link between air pollution and hospitalisations in Australia, and honestly, it hit very close to home for us.

The study found a direct link between air pollution exposure and increased cardio-respiratory hospitalisations across Australia. Researchers are now calling for stronger action, including phasing out new diesel vehicle sales and banning wood fires because of their impact on public health.

And while we often think about pollution as something “outside”, we think there’s a much bigger conversation missing from the discussion:

The air inside our homes.

Because the reality is this:

The Australian Academy of Science and associated indoor air quality research initiatives recently reinforced that:

“The majority of human exposure to air pollution occurs indoors, where people spend around 90% of their time.”

That statistic should fundamentally change how we think about housing.

If we spend around 90% of our lives indoors, then indoor air quality becomes one of the biggest environmental health factors in our lives.

And yet, it’s still rarely treated that way.

When Buildings Affect Your Health

For people who have never struggled with asthma or respiratory issues, it can be hard to explain how deeply air quality affects daily life.

A few years ago, when Simone’s asthma was badly flared up, everyday environments became exhausting.

Going into the city would often trigger coughing fits because of traffic fumes and pollution. Waiting at train stations made things worse. Windy days could leave her struggling because everything in the air felt amplified.

Even the office environment became a problem.

Whenever the ducted heating was running, it would trigger constant coughing. Eventually, working from home became the only option on colder days when the heating needed to be on. Looking back now, it completely changed how we think about buildings, health, and indoor environments.

Because many current homes are quietly making people sick.

Not intentionally — but through:

• poor ventilation
• condensation
• hidden mould
• stale indoor air
• smoke infiltration during bushfires
• and chemical off-gassing from materials

The Hidden Problem Inside Australian Homes

Outdoor pollution is only part of the story.

Many Australian homes also struggle with:

• condensation
• dampness
• poor ventilation
• hidden mould
• dust and airborne particulates
• stale indoor air
• and airborne pollutants entering the home

And mould in particular is far more common than many people realise.

Studies in Australia and New Zealand have repeatedly shown high rates of dampness and visible mould in residential housing. In many cases, mould is hidden inside wall cavities, roof spaces, behind furniture, or within poorly ventilated areas — meaning people are breathing unhealthy air without even realising it.

And mould is not just an aesthetic issue.

It’s a health issue.

Poor indoor air quality and mould exposure have been linked to:

• asthma flare-ups
• chronic coughing
• wheezing
• respiratory infections
• allergies
• sinus irritation
• fatigue
• headaches
• skin irritation
• brain fog
• sleep disruption
• and long-term respiratory issues

For vulnerable people — especially children, elderly people, and anyone with asthma or allergies — the impacts can be even more serious.

Why Passive House Matters

This is one of the reasons we care so deeply about Passive House and high-performance homes.

People often assume Passive House is purely about reducing energy use or lowering heating and cooling costs.

But one of the biggest benefits is actually the healthier indoor environment it creates.

A properly designed Passive House includes continuous balanced mechanical ventilation — often referred to as an HRV or MVHR system (Heat Recovery Ventilation / Mechanical Ventilation with Heat Recovery).

These systems constantly supply fresh filtered air into the home while extracting stale, humid air from bathrooms, laundries and kitchens.

And this is where things become incredibly important from a health perspective.

The incoming air is filtered.

That means significantly reduced:

• dust
• pollen
• outdoor pollutants
• traffic fumes
• smoke particles
• and even bushfire smoke entering the home

For asthma sufferers or people with allergies, that can make a massive difference to daily life.

Preventing Mould Before It Starts

These systems also help regulate indoor humidity levels — and that’s critical when it comes to mould prevention.

Because mould thrives in damp environments, condensation, and cold surfaces.

Passive House principles help address those conditions in several ways:

• continuous ventilation removes excess moisture from the air
• airtightness prevents uncontrolled humid air movement through the building
• high-performance insulation keeps internal surfaces warmer
• and the reduction of thermal bridges eliminates cold spots where condensation can form

That last point is hugely important and often overlooked.

In many standard Australian homes, thermal bridges create colder areas around windows, wall junctions, ceilings, slabs, or structural penetrations. Those colder surfaces attract condensation — and over time, that moisture can lead to mould growth.

In a properly detailed high-performance home, those cold spots are dramatically reduced.

Which means:

• less condensation
• less trapped moisture
• and far lower risk of mould forming in hidden areas

Healthy Homes Go Beyond Ventilation

The materials we put inside homes matter too.

Many common building products, paints, adhesives, cabinetry, joinery materials and flooring products release volatile organic compounds (VOCs) and formaldehyde into the indoor environment through a process known as off-gassing.

And again — if people spend around 90% of their lives indoors, these exposures matter.

That’s why healthier material selection is such an important part of creating healthier homes:

• low VOC paints
• low formaldehyde joinery
• healthier flooring products
• and carefully selected finishes

all contribute to better indoor air quality over the long term.

The Part People Rarely Talk About: Noise

There’s another aspect of high-performance homes that people often underestimate:

acoustic comfort.

The same airtight, highly insulated building envelope that improves thermal performance and indoor air quality also creates much quieter indoor environments.

For people living:

• near busy roads
• close to train corridors
• under flight paths
• or in dense urban environments

that reduction in outside noise can genuinely transform quality of life.

Homes Should Support Human Health

To us, healthy homes are about far more than just reducing energy use.

They’re about creating environments that actively support human health.

Homes that help people:

• breathe better
• sleep better
• recover better
• and feel better

And as Australia continues to deal with:

• worsening outdoor air pollution
• bushfire smoke events
• urban density
• traffic exposure
• respiratory illness
• and increasing awareness around mould and indoor health

we genuinely believe indoor air quality is going to become one of the most important conversations in our industry over the next decade.

Because homes shouldn’t just shelter us from the weather.

They should actively support our wellbeing every single day.