Design trends for modern buildings are setting high expectations for comfort, amenity, and sustainability. The emphasis on open spaces, indoor-outdoor flow, and open roofs and galleries, is creating a lot of complexity for engineers responsible for air flow and ventilation.

The first task is to analyse airflow through a building. Sophisticated computer modelling is required to give reliable predictions of the interaction between natural and artificial ventilation. When the ventilation systems are a component of fire safety design, the reliability of engineering predictions becomes a life safety issue.

There is a growing awareness of the complexity of analysing air flow in a building under such conditions, and the need for peer review to ensure the robustness of design. These are not limited to Building Consent applications; phrases such as “Sanity Check” are creeping into briefs – a slightly desperate sounding term showing how much planning effort is required.

With both fire and mechanical engineers on our team, S&T is well-placed to review the interaction of engineering systems. Some of the conflicts we find ourselves addressing include:

Occupied spaces immediately adjacent to an atrium may be subject to poor air flow if the occupied space ceiling zone and/or atrium are used as return air paths. These spaces may also be subject to noise intrusion from atrium activities and/or mechanical plant in the atrium. Fixed openings in the perimeter of the building for natural ventilation (as part of a mixed mode solution) may allow short circuiting of air flow when mechanical ventilation is used, and may (by short circuiting) reduce the effectiveness of a smoke extract in the atrium. Stephenson&Turner’s engineers offer a one stop shop for peer reviews and original design requiring close interaction between fire and mechanical systems. 

For more information please contact Paul Taylor at 09 920 9512 or ptaylor@stephensonturner.com.