I was wondering what people use as their tolerance for unmet load hours for LEED, this has been touched on before in some of the previous questions but I think it is a really interesting subject as you can't submit LEED EAp2 credit without getting your unmet hours down below 300 and with only 50 hours difference between the baseline and design case, the rules are very strict.
In EnergyPlus we can specify our tolerances and the default is a delta T of 0.2°C which is a very tight tolerance for unmet load hours. I have spoken with others and some software packages set their unmet load hours tolerance to around 1.8°F (1°C). The difference between these two values is enormous when it comes to deciding whether a zone has its tolerance met. Specifically, does anyone have any guidance from LEED as to what value to use. Clearly we could all use a delta T of 10°C and have no unmet hours but the systems are likely not doing what they are supposed to and the points would vary wildly.
