Passive and Mixed Mode Design

Passive ventilation is the use of wind and thermal buoyancy to introduce fresh air into an indoor space with the use of trickle ventilators, windows, and louvres. Mixed mode ventilation utilizes a combination of natural ventilation and traditional mechanical ventilation to meet Australian code requirements of fresh air.
Example of a trickle vent.
The constant ventilation of fresh air into an internal environment reduces the concentration of nitrogen dioxide (NO2), carbon monoxide (CO), and volatile organic compounds (VOC). The introduction of fresh air can increase indoor environmental comfort, which can improve productivity and wellbeing within the space.
Passive and mixed mode ventilation are also used to control the temperature of the space, and suitability can vary from different climates. Poor design can lead to draughts in winter, and too many open windows may undermine the effectiveness of the mechanical ventilation system. Additionally, passive and mechanical ventilation located adjacent to railways, heavy traffic, industrial facilities, carparks, or mechanical exhausts can introduce noise or excess contaminants into the space.
SEED is able to provide advice and compliance to Australian standards in the use of passive and mixed mode ventilation.

SEED provides the following services for passive and mixed mode ventilation design:

  • Thermal comfort modelling,
  • Air quality analysis,
  • Compliance to Australian Standards,
  • Passive and mixed ventilation detailed design, and
  • Natural ventilation advice.

When used correctly, passive and mixed ventilation designs can greatly reduce running costs and can improve indoor environmental conditions. SEED uses these concepts regularly on all classifications of buildings to achieve efficient design and compliance to the National Construction Code and Australian Standards.