Tiled Traditional Roof >15° – 75°
Primary insulation layer NOT parallel to roof plane Tiles >15° – 75°
All VENT Systems technical advice presents BEYOND COMPLIANCE of the National Construction Code 2025 Vol 1: F8D5 & F8D6 / ABCB Housing Provisions Standard 10.8.3 to ensure mitigation of the risks associated with internal moisture in the roof cavity. BEYOND COMPLIANCE solutions go above and beyond the requirements of the NCC 2025, addressing critical areas such as ensuring unimpeded airflow past insulation. These measures are essential for maintaining optimal conditions within the roof space and minimising the potential for moisture-related issues.
VENT Systems offers a range of solutions compliant with AS3959, AS4200 as well as NCC2025.
For a Traditional Pitched Roof >15° – 75° NCC2025 requires “7,000mm²/lm at Low Level and 5,000mm² /lm at High Level.”
FOR COMPLIANCE:
Application for trussed/gable/Hipped roofs
Low level: Application at Eaves or Box Gutters
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- Our G750N Over Fascia Vent 7.5mm guarantees a calculated airflow of 7,500mm²/lm, ensuring compliance effortlessly at Eaves or Box Gutters.
High Level: At Apex/abutment/parapet – Within 900mm of the perpendicular height of the Apex of the roof
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- Our G630 Lap Vent is specifically designed to assure compliance and ease of installation, guaranteeing a calculated airflow of >3,000mm²/vent.
ABOVE COMPLIANCE:
Our G502 Roll Panel Vent compliance with NCC2025 ensuring a 20mm gap above the primary layer of insulation & ensures unimpeded airflow through the eaves.
For bespoke or complex designs there are numerous alternatives that can beconsidered. Contact our specialist team for further assistance.
DISCLAIMER: Product combinations specified within Vent Systems Pty Ltd (ACN 682 448 997) (Vent Systems) technical documentation are designed to mitigate the risk of moisture accumulation and condensation when installed correctly. Unless otherwise indicated, Vent Systems’ individual products or product combinations generally comply with relevant requirements of the Australian Standards and National Construction Code (NCC). However, compliance with NCC minimum requirements alone may not provide adequate moisture and condensation management per sae. Vent Systems can provide professional and tailored advice as to the suitability, specification and installation of ventilation systems. Except to the extent that we have provided tailored advice, to the fullest extent permitted by law, Vent Systems accepts no liability for losses, damages or defects arising from the specification, installation or performance of its products, and does not guarantee any condensation control, moisture mitigation or overall building performance.
G750N – Over Fascia Vent
The VENT Over Fascia Vent – G750N is the most practical and cost-efficient way to ventilate the eaves on traditional roofs pitched at 15 degrees or more, delivering 7,500mm²/lm of free airflow. Paired with the VB20 Ventilation & Drainage Batten it reaches 22,000mm²/lm, which is enough to meet NCC airflow requirements for pitches under 15 degrees. It is easy to install, sits discreetly hidden behind the spouting, suits both timber and metal fascias, and works with no moving parts or energy use.
G502 – Roll Panel Vent
The VENT Systems Roll Panel Vent G502, also known as an Eaves Baffle or Insulation Guard, holds a 25mm air gap between the insulation and the roofing underlay so air flows freely through the eaves into the roof cavity. Insulation batts can sit full depth above the wall plate with no gaps, cold spots or heel height adjustments, protecting the Energy Star rating that poor eaves insulation erodes. Suitable for concrete and metal roofs, it guarantees compliance with NCC 2022 Vol 1 F8D5 and ABCB Standard 10.8.3.
G630 – Lap Vent
The VENT Systems Lap Vent – G630 releases warm, moist air from the roof void using the natural convection of rising warm air, delivering 3,000mm²/unit of free airflow with no moving parts or energy use. It is applied to the highest layer of horizontally laid membrane or sarking within 900mm of the high point of the roof to comply with NCC requirements, needs no tools or fixing accessories, and requires no change to ridge capping, which makes it equally suited to new builds and retrofits. The G630 can be used in isolation or as part of a proprietary ventilation system, and as a high level vent it performs best paired with low level eaves or over fascia ventilation.
G1275 – Eaves Comb Filler
The Eaves Comb Filler G1275 uses flexible fingers that adjust to fill the gaps left by profiled concrete tiles or metal roof cladding, keeping birds and large insects out of the roof while air still flows freely into the cavity. It is a cost-effective replacement for purpose-made fillers that block airflow above the underlay and trap moisture from leaks or dew point. Supplied in 1m lengths, it fits over VENT Systems Over Fascia Vents or directly to timber or metal fascias. For BAL-0 zones only.
