Sustainability and the building environment

¶ … Ventilation

With oil topping a hundred dollars a barrel, it is not surprising that engineers and architects are seeking better designs for structures of all types. Such "greening" efforts extend across-the-board in architectural design today, and the authors of "Natural Ventilation" report that significant innovation has been accomplished in recent years in improving the ventilation of buildings. Certainly, modern heating and ventilation systems have allowed humans to expand the range of habitable climates to include sites such as Las Vegas and Phoenix that were formerly hostile to people because of their harsh temperatures and arid conditions. Many of the buildings that emerged from these expansions into these inhospitable regions precluded the use of any natural ventilation techniques because they were closed systems that relied on massive mechanical systems that were effective at conditioning air but at an a high price in terms of human productivity and rising energy costs.

By sharp contrast, the authors of "Natural Ventilation" emphasize that the introduction of computer-based technologies has provided opportunities for the use of both passive and active systems that take maximum advantage of the natural ventilation that is always available to some extent. The techniques involved in optimizing natural ventilation are also fairly straightforward and a part of the continuing drive to make buildings more cost-efficient for their owners and comfortable for their occupants. Furthermore, natural ventilation systems can be used by themselves or as part of a building's existing or planning ventilation system.

In fact, the use of such systems provides a number of cost-saving advantages from start to finish. The article reports that the integration of systems such as building envelope (this is the view of the entire building as an integrated and interrelated whole), massing, glazing and internal loads, these techniques represent an integral part of a comprehensive architectural-engineering approach to providing better performing buildings for less cost. These are major selling points in an era characterized by skyrocketing energy costs, of course, but the authors point out that there are other advantages that accrue to the use of these natural ventilation techniques as well. People are naturally attuned to their environment and despite having worked in buildings with closed ventilation systems in the past, studies indicate that humans are more comfortable when there are minor fluctuations in the ambient temperate that reflect the corresponding weather outside, and natural ventilation restores this natural balance.

There are a number of factors to be considered when designed buildings to take maximum advantage of natural ventilation resources, though, particularly when these natural ventilation techniques are used in combination with solar energy considerations, including the prevailing wind direction and speed, typical levels of humidity, positioning of the building and its contents in relationship to the sun, window placement, and so forth. By taking advantage of whatever is available at a given building site, engineers and architects can help create a building that helps people become more productive while reducing initial building costs and providing enormous long-term savings in mechanical heating and ventilation systems. Indeed, the authors of "Natural Ventilation" emphasize that cost savings of between 50 and 100% can be achieved, and in some cases, air conditioning systems can be eliminated altogether.