Air Curtains vs. Vestibules: How to Maximize Your Space
How much do you want to spend? How much space can you afford to lose?
The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) has adopted Standard 90.1-2019, Energy Standard for Buildings Except Low Rise Residential Building that dictates that commercial air curtains in doorways are approved alternatives to space-encroaching vestibules in most commercial buildings.
Designing a commercial space to make optimal use of the square footage is a principal driver and leading business objective. With commercial space lease rates expected to continue to rise in the new decade and beyond, sales per square foot and rent per square foot are calculations that can change the profitability equation if not managed well.
Finally, there is additional support for the owner/operator to design a space that advances their commercial interests while eliminating the space-encroaching vestibule that reduces usable square footage and forces designs that infringe on profitability.
American Society of Heating, Refrigerating and Air-Conditioning Engineers adopts Standard 90.1-2019 dictating air curtains can replace vestibules
DOWNLOAD ARTICLECHOOSE YOUR MARS AMCA CERTIFIED AIR CURTAIN SOLUTIONS
This new standard, which applies to retail, healthcare, hospitality, office and other commercial spaces, dictates that commercial air curtains (also known as an air door or a fly fan) must be approved and tested according to ANSI/AMCA Standard 220 for assurance of a 122-m per minute airstream velocity at the floor for complete protection. Mars offers AMCA-certified air curtains (also known as a fly fan) that are also independently tested to meet Mars rigorous standards.
STUDIES PROVE AIR CURTAIN EFFECTIVENESS TO REPLACE VESTIBULES
Studies establish* that whole building annual energy consumption, modeled with the air curtain door, is less in all climate zones when compared to the modeled vestibule door. The modeled air curtain door can reduce energy consumption by 0.3 percent to 2.2 percent in colder climate Zones 3-8, but marginal for Zones 1 and 2, as no changes were made to the operating characteristics of the air curtain. The study also established that the building entrance orientation, frequency of use and the balance of the building HVAC system (pressure) affect air infiltration/exfiltration, and the overall energy performance of the air curtain.
* Investigation of the Impact of Building Entrance Air Curtain on Whole Building Energy Use,” was conducted by Liangzhu Wang, PhD, Assistant Professor at the Department of Building, Civil and Environmental Engineering of Concordia University, Montreal, Canada.
A recent study published by AMCA International evaluated the effectiveness of air curtains (commercial air curtain) and confirmed that when compared to a vestibule, air curtains consistently meet or outperform vestibules in energy savings. The most recent study, “Investigation of the Impact of Building Entrance Air Curtain on Whole Building Energy Use,” was conducted by Liangzhu Wang, PhD, Assistant Professor at the Department of Building, Civil and Environmental Engineering of Concordia University, Montreal, Canada. Dr. Wang compared the cost effectiveness of an air curtain mounted over a single-entry door versus a vestibule using an approach that integrated three types of modeling software: ANSYS Fluent for CFD simulation, TRNSYS for energy modeling, and CONTAM for modeling building air pressure and infiltration. The study illustrated that whole building annual energy consumption, modeled with the air curtain door, is less in all climate zones when compared to the modeled vestibule door. The modeled air curtain door can reduce energy consumption by 0.3 percent to 2.2 percent in colder climate Zones 3-8, but marginal for Zones 1 and 2, as no changes were made to the operating characteristics of the air curtain. The study also established that the building entrance orientation, frequency of use, and balance of the building HVAC system (pressure) affect air infiltration/exfiltration, and the overall energy performance of the air curtain.
The IECC is published by the International Code Council (www.iccsafe.org), “a member-focused association dedicated to developing model codes and standards used
| BUSINESS OBJECTIVE | VESTIBULE EFFECTIVENESS | MARS AIR CURTAIN EFFECTIVENESS |
|---|---|---|
| PROTECT CLIMATIZED INTERIOR AIR (HEATED OR COOLED) | SOMEWHAT Can be effective if all doors remain closed almost all the time | EXCELLENT, WITH OBSTRUCTION-FREE SUPPORT FOR FREE & RAPID PASSAGE |
| PROTECT INTERIOR FROM FLYING PESTS | SOMEWHAT Open doors allow for pest transfer | SUPERIOR PERFORMANCE, EVEN WITH OPEN DOORS |
| KEEP BUILDING INTERIOR CLEAN | MAYBE Depending on volume of traffic and door opening | EXCELLENT PROTECTION, EVEN WITH OPEN DOORS & WIND |
| SAVE ENERGY COSTS | SOMEWHAT Effective If all doors stay closed | SUPERIOR PERFORMANCE |
| FREE FLOWING TRAFFIC | NO | YES, WITH NO OBSTRUCTION |
| EFFECTIVE TO 122-M PER MINUTE AIRSTREAM (as required by code) | NOT APPLICABLE | YES |