What is diversity factor in HVAC systems?

Answer 1

In large buildings with many zones and exposures the building peak load generally changes as the sun load shifts during the day.  However with VAV systems, the central heating and cooling (HVAC) equipment can be selected for the maximum building’s peak load (black load) that occurs either once during the summer (cooling peak load) or daily.  As each VAV terminal air unit is sized for the peak load of the spaces it serves, the total capacity of all of the VAV terminal air units would be much greater than the capacity of the central HVAC systems and fans.  The diversity factor is the ratio (or percentage) obtained when the total output capacity of the building HVAC system is divided by the total capacity of all Terminal Air Units connected to the system. This factor may vary considerably, but often is in the 0.7 to 0.8 (70 to 80 percent) range.

Answer 2

Diversity factor applicable depends on the usage of buildngs

example like : Hotels - aprox 70 to 80 %

hospital - approximate - 60 to 70%

schools varies and depends on usage

Answer 3

Is there any methodical calculations to scientifically determine diversity factor or is it judgemental only? If there is a 62 storey high rise building with offices and apartments and having central absorption and centrifugal chillers and AHUs on each floor.