Experts in passive ventilation, Vent have designed a three part ventilation system for cold roof pitches over 30º to prevent moisture accumulation in the roof cavity. The system features a combination of Vent's Over Fascia Vent, Roll Panel Vent and Ridge Vent which work together to establish unimpeded airflow through the roof cavity.
The first part of the system, the Over Fascia Vent – G1200N, provides airflow of 10,000mm² per linear metre into the roof cavity — discreetly ensuring a positive airflow into the roof space. To ensure that this airflow is not blocked by insulation, the Roll Panel Vent – G502 is applied over the trusses. This creates a guaranteed passage of 50mm between the underlay and the insulation.
As moisture accumulation commonly occurs in the apex of roofs above 30º, the ridge requires ventilation. The final component of the system is the Vent Ridge Vent – RV10P which is applied to the apex of the steel roof to effectively release air, ensuring continuous airflow through the roof space. The combination of these three components provides a complete passive ventilation system through the roof cavity.
This system for 30º roof pitches is one of a series of ventilation systems Vent has designed to meet the specific challenges of different cold roof pitches. Each system is easy to install, cost-effective and requires no further maintenance — using free and fresh air to work passively.
"Vent systems are based on international best practice and have been proven to reduce internal moisture in roof cavities," explains James Johnston, Commercial Manager of Vent. "Applying Vent systems and products will improve a building’s air quality, improve durability and mitigate the risk of internal moisture build-up and associated issues caused by internal moisture."
Johnston recommends using the Vent passive ventilation systems to complement current mechanical systems. "Rather than relying on the filtration of stale, moist air that is currently found in an airtight roof cavity, VENT ventilation systems feed fresh air into the roof cavity. This results in improved air quality to the habitable areas."
By incorporating Vent's complete passive ventilation system into building design, the risk of interior moisture is significantly reduced, removing the problems associated with condensation in the roof space.