Performance based approached for ventilation started to be used in Belgium in 2008 in the context of EP regulation. Until 2015, demand controlled ventilation (DCV) systems were considered as “innovative” products and were not directly taken into account in the EP calculation method. Their energy performance was then considered through a principle of equivalency. A first performance based approach was developed in this frame.
As DCV systems became more and more common, it became considered as a “mature” technology and then was included in the basis EP calculation method in 2015. The reduction factors of the method were determined using an updated method based on the existing equivalency approach.
This experience has been then used in many research projects. Among these projects, the recent PREVENT project aimed at the elaboration of new performance criteria and design rules (simplified rules) for ventilation systems in dwellings. This project emphasized also the need, in complement to simplified rules easily applied for simple systems, to have performance based approaches to be able to evaluate the performances (IAQ and Energy) of some more complex systems, such as natural ventilation systems, some DCV systems, etc. Performance criteria were used to compare different ventilation systems, whether they were using DCV or not.
The challenges are however still big and experience acquired through these various steps are of great value. The aim of this paper is to illustrate some challenges and limitations of such performance based approaches for ventilation system.