Installation process and benefits of Vent-a-Roof on Residential Metal Roof


Fresh outside air is taken in either through soffit vents or in through the system itself. This cooler air rises from these intake points and mixes within the ceiling or building space to create a natural flow of air that leaves the hot air escaping through the top of the ridge/skillion.

Simultaneously, a positive airflow also crosses over the ridge of the house creating a negative pressure which pulls air out from the ridge vent. Effectively, two thermal effects create a continuous flow of air allowing cool air into the roof/building space and extracting hot air.


Roof ventilation has become increasingly important to maintain high liveability, health and safety standards in Australian buildings. There are five key reasons to ventilate your roof.

Reduce Temperature

Roof ventilation allows hot, stagnant air that builds in the roof space to disperse to cooler outside air, which decreases the overall temperature of the structure.

Cost and Energy Efficient

Decreased temperature means less need for costly air-conditioning systems. A well-ventilated roof means air-conditioning ducts can operate at lower temperatures, therefore using less power to cool the structure.

Condensation Management

In Australia’s diverse climates, stagnant air in the roof can cause condensation to form. Because ventilation increases airflow, the chance of condensation forming is reduced. This is a preventative measure against the build-up of mould, which is a national health hazard.


The National Construction Code has been updated to reflect the Australian Building Code’s Board’s actions to reduce condensation and increase energy efficiency. Roof ventilation reduces condensation and increases energy efficiency and is therefore an important aspect of these changes.

  1. Reduce Internal Pressure

Large commercial buildings require ventilation to ensure internal and external pressures are maintained to withstand natural elements and ensure structural integrity

Furthermore, positive airflow across the ridge of the house creates a negative pressure which pulls air out from the ridge vent system and brings in fresh air from the intake vents below. In either calm or windy conditions, the entire ceiling cavity is vented by a constant flow of cooler, dryer outside air. These key factors create and maintain effective and efficient air flow.


Cost Comparison

Whirlybird: $180-$300 fully installed
Vent-A-Roof™: $50 – $250 fully installed
2.5m ridge – airflow equivalent of 1 whirlybird
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