Co-working space has been growing significantly in the past few years. Compared with traditional office spaces, co-working space typically offers more efficient layouts and higher utilization of the available square footage, with more celluralized office spaces across the floor to cater to various occupant needs. Globally, there is no dedicated ventilation code requirement or guideline for co-working spaces and most of co-working space use the traditional office buildings ventilation code for building design and calculations. In this article, we will investigate the office building ventilation codes in two main regions of the world – Asia Pacific (APAC) and North America (NA) to show a comparison between various countries and how these impact the growing co-working space designs. The main focus for ventilation code requirements is typically two-fold - how much CFM of outside air is required per person, and then how the code calculates the number of people to include in the design. It is interesting to notice that the ventilation rates calculated by following local codes from different regions vary from each other. Providing more than intended outside air rates could result in more cooling load, filtering demand, larger HVAC space needs and more energy in HVAC systems. Further, bringing in more Outside Air than is required for the real-time use of the space is even more of an issue in regions with relatively higher percentages of contaminants in the outdoor air - poor outdoor air quality and massive ventilation rate will result in high air filtration requirements and excessive energy consumption in ventilation systems. This article aims to raise awareness of the impact of office building codes to co-working designs and some of the key design impacts that these impose on existing building stock. D-VC-20-C046