Changes to ventilation requirements in the National Construction Code 2019

MENA Award Winners

The National Construction Code 2019 Volume Two has introduced a new section titled ‘Condensation Management’ that will include a clause titled Ventilation of Roof Spaces.

This change requires that exhaust systems installed in a bathroom, sanitary compartment, or laundry are either discharged directly to external air OR discharged into the roof space - if discharged to the roof space, then the required open area of the roof space ventilation is calculated based upon the ceiling area directly under/attached to the roof/attic space of the home.

How to Comply with the National Construction Code 2019
A) Exhaust directly into the roof space and use Bradford’s natural roof ventilation in combination with eave vents to exhaust moist air
B) Direct ducting of internal wet rooms (bathrooms, kitchens & laundries) to outside air

Bradford Ventilation Solutions for NCC2019
The following table provides roof space ventilation solutions for residential homes with roof pitch >22° where the exhaust from a bathroom, sanitary compartment, or laundry is discharged to a ventilated roof/ attic space.

Important Selection Considerations:
1. ‘Total Ceiling Area’ is defined as the total ceiling area directly under the roof/attic space.
2. Where the roof pitch is ≤ 22°, the number of ventilators and eave vents specified must be doubled for the same ceiling area.

NCC2019 recommended ventilation levels

How to Comply with Clause “Ventilating through regularly distributed openings to outside air”

Roof ventilators and eave vents must be installed with even spacing between each unit. An example of how this could be applied in several basic roof applications is demonstrated below:

NCC2019 recommended ventilation levels

Benefits of using Bradford’s Natural Ventilators to comply with NCC2019
• Eliminates the complexity of routing ducting through the internal structure of the home
• Reduces coordination of different trades required to connect ducting to appliances
• Provides the added benefits of heat and moisture management to the consumer

Bradford Product Solutions

WindmasterBradford’s WindMaster is a 300mm, lightweight, aluminium natural wind ventilator suitable for metal and tiled roofs. When fitted with Bradford’s sparkguard, WindMaster is suitable for bushfire rated regions up to and including BAL-40. WindMaster DTC is a variant of WindMaster suitable for Cyclonic Region C in Australia. WindMaster has a 15 year warranty and is available in 27 colours to suit most roof types.
Note: Addition of Sparkguard increases number of WindMasters required on roof - ask Bradford for advice. Learn more about WindMaster here

SupaventBradford’s SupaVent is a 250mm, natural wind ventilator with a UV and temperature stable plastic head and is ideal for tiled roofs as only one tile is required to be removed for installation. SupaVent’s stainless-steel bearings make it ideal for homes close to salt spray. SupaVent has a 15 year warranty and is available in 16 colours to suit most roof types. Learn more about SupaVent here.


 Bradford Eave Vents
Poly Eave VentBradford eave vents are designed to work in conjunction with roof vents to allow external air to be drawn into the roof space to improve cross flow ventilation. This helps roof mounted vents to work more effectively and efficiently. Bradford’s metal eave vents are suitable for bushfire rated regions up to and including BAL-40. Learn more about Eave Vents here.

02 Apr 2019
Contact us
General enquiries:
1300 858 674
Case studies

Browse our commercial & industrial case studies to see how Edmonds can help your project

Sensitive Choice partner