US officially approves air curtains as green alternative to vestibules
In the United States, the Air Movement and Control Association International, Inc. (AMCA International) has officially announced that air curtains are an approved alternative to vestibules, an article on Green Lodging News reports.
Vestibules are used in buildings to reduce air infiltration and regulate temperatures inside the main building. However, they do have their negative aspects; they can be unsightly, take up valuable floor space, and can cause difficulties if you need to evacuate the building in a hurry. This is where air curtains can offer the perfect solution - they minimise the infiltration of air contaminants and maintain a desired temperature inside the building, whilst allowing business owners to maintain floor space and eliminating the inconvenience of having to go through two doors. For some time now, architects and engineers have been aware that air curtains are a low-cost, energy-saving alternative to vestibules, but this is the first time that they have been approved as an official alternative in the US energy code.
Having passed numerous studies, the new provision will be added to the 2015 version of the International Energy Conservation Code (IECC), and it has also been accepted by the International Green Construction Code (IGCC).
The most recent study, conducted by Liangzhu Wang, PhD - assistant professor at the Department of Building, Civil and Environmental Engineering of Concordia University, Montreal - compared the effectiveness of an air curtain installed over a single-entry doorway, against a vestibule entryway. The findings revealed that the whole building's annual energy consumption was less in the model featuring the air curtain door, with energy use being reduced by 0.3-2.2%, depending on the area. Other similar tests have shown that air curtains consistently meet or outperform vestibules in energy savings, the article notes.