The Applicability of Natural Ventilation - Technical Editorial

It is only comparatively recently, since the development of mechanical ventilation and refrigeration, that it has become possible to completely control the air quality and thermal environment inside buildings, irrespective of outdoor conditions. However, such control is an energy intensive process that requires reliable energy supply. Concerns about future security of conventional supply, combined with the impact of fossil fuel emissions on global warming, has resulted in renewed emphasis on building energy efficiency. In achieving improved performance, natural ventilation and passive cooling methods are becoming important components of modern architecture in many countries.  This editorial reviews some of the issues and barriers associated with natural ventilation and outlines recent progress. It also summarises the European Energy Performance of Buildings Directive (EPBD) which, again, has an important impact on ventilation methodology in Europe. It is concluded that, for various reasons, natural ventilation is having a difficult time in gaining regulatory acceptance, even although there is strong demand for passive solutions from both private and public bodies. In the United Kingdom it is shown that, although a number of key official agencies strongly support the use of natural ventilation, the current Building Regulations and moves towards zero carbon buildings incorrectly acts against the benefit of natural ventilation. This, it is argued, is because a holistic view of total carbon emissions is not being taken into account.  Ultimately it is the absolute CO2 emissions that impact on the environment but this is largely missing from the narrow objectives set by various regulations, standards and calculation techniques.