Green Buildings do make a difference.
It has been argued that the public cant tell the difference between a building and a green building, from the outside buildings “look” the same. And advocates have argued the improved productivity is the key metric, although measuring that is a really challenge. thats why a piece in The Guardian caught my eye, it tends to support the idea that better buildings, i.e. green buildings, are better for its occupants, and employers, less sick days being one of the claims.
It is commonsense in my view, people are more productivity/happy in a good environment, and for work that means buildings having better features than bog standard buildings built for minimum code.
The typical minimum code only covers the basics, although that is changing, there are few, if any, environmental requirements. Check the fresh air for example, I have seen commercial building brochures with fresh air provided (enough for 100 occupants) but the floor plan indicates 150 workstations, fresh air per person is not mentioned. We have seen this before, during past energy efficiency drives, fresh air was curtailed to such an extent that sick buildings were created, therefore it is critical that HVAC systems are energy efficient and provide the necessary comfort, including sufficient conditioned fresh air. In Hong Kong with tropical summers heat, most often a simple central PAU (fresh air unit) is the preferred solution, with simple on/off control. However this model needs to deliver 100% of the fresh air requirement, even periods of low occupancy.
Considering larger buildings, a larger diversity is predicted, think about hotels, often the central fresh air system is designed to provide 100% fresh air, irrespective of the number of occupants, and where the hotel occupancy fluctuates, say 50% occupancy, there is 50% too much fresh air conditioned and filtered.
So i agree Green Building systems are certainly a step in the right direction, however more studies are needed to define and assess those extra intangible benefits, and hopefully it will include productivity.
by John A. Herbert, BEAM Professional