After starting this thread I found the following in Trane's VAV system design manual. If the heat loss of perimeter wall space exceeds 450 btu/ft of outside wall, an under-the-window, or baseboard, heating system is typically used. If the heat loss is between 250 and 450 btu/ft of outside wall...
I am trying to remember amount of exterior wall heat loss per foot (btu/ft) when perimeter heat (finned tube, radiant panels, etc.) should be used to supplement overhead heat. I know it is somewhere in ASHRAE but I cannot find it. Can you help me? This is for a health care application.