That’s why we’ve been hearing more stories in the news and the industry about mouldy new-builds, overheating homes, and moisture in odd places like ceiling cavities. But why are we seeing these problems now? What’s changed in the way we construct modern homes?
Structural changes
The first challenge is increased airtightness. This keeps homes warmer in winter but significantly reduces the natural air that flows into our homes. And less air movement means more overheating and internal moisture.
The second culprit is other design constraints. Modern homes are often built with minimal eaves, poor window placements/ openings, and limited air pathways. These limit the effectiveness of natural airflow and ventilation when airing out a home.
This lack of natural air movement means that moist, hot air builds up within a new home, leading to the overheating and mould that we’re seeing today.
The solution here isn’t to walk back recent building innovations. Instead, we need deliberate mechanical ventilation in every home to expel the moist, overheated air to keep those spaces healthy and comfortable to live in.
Lifestyle changes
The second half of the problem is lifestyle changes. Recent BRANZ research indicates that natural and intermittent ventilation are incompatible with modern lifestyles. To properly ventilate a home, occupants must be very diligent about opening windows and using extraction fans. This includes leaving them open/ running for long enough, something that many occupants are unwilling to do due to security, privacy, or energy efficiency reasons.
The solution to this is either a system that runs automatically, or constantly, so it doesn’t rely on occupant actions to effectively ventilate.
The solution: Continuous mechanical ventilation
When taken together, recent changes in housing and lifestyles mean modern homes need continuous mechanical ventilation to reliably manage moisture and overheating in modern homes. As homes become more airtight, natural and intermittent ventilation will continue to fall short. Continuous extraction is no longer an upgrade, but a practical response to how homes are now built and used.
What’s in it for your business?
Continuous is becoming the new standard in home extraction ventilation. As more research is published, Kiwis will demand continuous ventilation solutions. Going continuous now enables you to get ahead of legislation and your competitors to future proof your business.
Get repeat business from happier customers. Position yourself as a trusted advisor by meeting customer needs consistently. Continuous extraction is the ideal method to meet customer needs thanks to simple building code compliance and by not having to worry about user error.
Grow your business with more higher value products, and less callbacks. Move customers from single-room extraction to whole-home ventilation solutions. On the flipside, take user error out of the equation to reduce unnecessary call-backs.
What continuous products should you use?
Simx has an extensive range of continuous ventilation solutions available, available at your local Active Electrical Suppliers Ltd branch.
To simplify things for you, we’ve made a quick reference guide for where each fan is best used:
Modern homes are more airtight and energy efficient than ever, but this has increased the risk of moisture, mould, and overheating. Continuous mechanical ventilation provides a reliable solution by maintaining healthy airflow without relying on occupant behaviour. For building professionals, adopting continuous ventilation now can improve home performance, reduce callbacks, increase customer satisfaction, and help future-proof projects against changing expectations and industry requirements. This article, published in the March 2026 edition of Marketplace, has been repurposed with permission from Simx.
This article, published in the March 2026 edition of Marketplace, has been repurposed with permission from Simx.