How to Improve Indoor Air Quality in Your Home

As an architect and healthy home consultant, I’ve seen firsthand how poor indoor air quality (IAQ) impacts health, comfort, and even energy efficiency. In Australia, our homes face unique challenges—bushfire smoke, high humidity, and extreme temperature shifts—all of which affect the air we breathe indoors.

Natural light and ventlation

The good news? You don’t have to build a Passive Haus to start improving your air quality today. Small, simple changes can make a big difference.

1. Remove Shoes at the Door

One of the simplest ways to improve indoor air quality is to leave your shoes at the door. Shoes track in:

• Dirt, pesticides, and heavy metals from roads and gardens.

• Allergens like pollen and mould spores.

• Bacteria and viruses from public places.

A shoe-free entryway with a bench and storage makes this habit easy for everyone in the household.

2. Dust and Vacuum Regularly (With a HEPA Filter Vacuum)

Dust isn’t just an eyesore—it’s a major source of indoor pollution, often containing VOCs, allergens, and even microplastics (source). Regular cleaning can significantly reduce these contaminants.

• Use a bagged vacuum with a True HEPA filter to capture fine dust and allergens. Bags mean the dast is captured and not redistributed when you empty the vacuum.

• Damp dust instead of dry dusting to prevent particles from becoming airborne.

• Wash bedding and curtains regularly, as they trap dust mites and allergens.

  
  

3. Let Fresh Air In—But Be Smart About It

While natural ventilation is great, it’s important to be strategic about when and how you open windows:

• Open windows early in the morning when outdoor pollution is lowest.

• Use flyscreens to prevent pollen and insects from entering.

• Close windows during high-pollen days if you suffer from allergies.

Natural Ventilation is one of the best ways to maintain healthy indoor environments

4. Choose Low-Toxic Flooring and Furnishings

Carpets and synthetic materials trap and release VOCs, dust, and allergens. If you’re selecting new flooring, choose;

• Cork flooring – a natural, sustainable option that resists mould and is free from synthetic finishes.

• Solid timber or engineered timber with non-toxic finishes.

• If you can't live without carpet, look at wool rugs over synthetic carpets to reduce VOC exposure.

  
  

5. Use Low-VOC and Non-Toxic Building Materials

If you’re building or renovating, opt for:

• Low-VOC or VOC-free paints (e.g. natural mineral-based options).

• Formaldehyde-free plywood and cabinetry.

• Solid timber flooring instead of engineered boards with toxic glues.

  
  

As an architect, I always specify natural, breathable materials to minimise indoor pollution while improving thermal comfort.

6. Improve Airtightness to Prevent Mould and Pollutants

Airtight construction is a core principle of Passivhaus design and a key factor in controlling IAQ. Poorly sealed homes allow pollutants, humidity, and bushfire smoke to enter unchecked. To improve airtightness, consider:

• High-performance membranes instead of basic building wraps.

• Taped and sealed joints to prevent air leakage.

• Well-sealed windows and doors with double or triple glazing.

  
  

7. Install a Mechanical Ventilation System with Heat Recovery (MVHR)

Unlike most traditional Australian homes, which rely on uncontrolled air leaks for ventilation, Passivhaus homes use an MVHR (mechanical ventilation with heat recovery) system. This system constantly exchanges stale indoor air with fresh, filtered outdoor air, removing pollutants, excess moisture, and carbon dioxide.

By installing an MVHR system, you can:

• Filter out allergens like pollen and bushfire smoke.

• Maintain optimal humidity to prevent mould growth.

• Reduce heating and cooling costs by recovering energy from outgoing air.

8. Monitor and Maintain Your Home’s Air Quality

Even the best home design requires ongoing maintenance to maintain healthy indoor air. Here’s what to do regularly:

• Replace air filters in ventilation and purfiers systems every 3-6 months.

• Check for leaks or condensation in bathrooms and kitchens.

• Install leak detection devices under appliance braided hoses.

• Use air quality monitors to track CO₂, humidity, and VOC levels.

Creating a healthy indoor space can start today with just a few simple steps

Final Thoughts

Improving IAQ isn’t just about opening windows—it requires intentional design choices and daily habits. Whether you’re building a Healthy Home, Passivehaus, or just making small upgrades, focusing on airtightness, ventilation, and non-toxic materials will ensure your home is a true sanctuary for health and well-being.

If you’d like expert guidance on designing a home with superior indoor air quality, let’s chat. As an architect specialising in healthy home design, I can help you create a space that’s beautiful, functional and supports well-being.