Hello All,

I'm wondering if anyone has any experience with the LEED 2009 daylighting
calculations (IEQ 8.1). I'm working on evaluating spaces using DiaLux
(option 1). There are a number of inconsistencies between the various
compliance methodologies.

Option 1 - Simulation: This method requires using a clear-sky condition,
even if clear-sky conditions are rare in a given climate, and require
calculation at 9am and 3pm
Option 2 - Prescriptive: This method looks only at window and room
geometry, and does not take into account internal surface reflectance,
orientation, external shading, or sun angle at the particular lattitude
Option 3 - Measurement: no time of day or weather requirements are given for
measurement. Measurement could be accomplished at any time of day, any time
of year, and under any sky conditions.

With option 1, there is a requirement to model the space at both 9am and
3pm. I am a little unclear as to whether it is required to take an average
of the compliant areas between the two, or if the compliant area is
exclusionary.

Also, thoughts/opinions on the inconsistencies between the methods?

Thanks,

--
Karen