The coronavirus thrives inside. A Hong Kong paper found that of over 7,000 COVID-19 cases, only one outbreak was contracted outdoors. In Seoul, an infection cluster was so concentrated that even on a 19-floor building, the outbreak was contained to just one floor, and almost entirely on one side of that floor. The data seems to indicate that infections occur in dense inside areas with shared airspace, compounded by recirculating that air — the definition of a modern office building.
Over the past decade, the density of office buildings has increased in a bid for ever-increasing efficiency. The move from cubicles to open planning drastically decreased the average space per employee in an office. The average cubicle is usually between 6 feet by 6 feet and 8 feet by 12 feet. A standard office desk for an open plan is almost half that, typically 5 feet wide and 2.5 feet deep. Another side effect of open planning was more people sharing the same air with fewer physical barriers.