Dear all,

LEED for Schools 2009 requires that 75% of classrooms be adequately day lit.

Say I have 40 classrooms. The requirement is that VLT*WFR is between 0.15 and 0.18

1) Should I check classroom by classroom for compliance (either yes or no), and then if 30 classrooms show compliance (lie in the range of 0.15-0.18), then I can be awarded 1 credit?

OR

2) Should I do the analysis of each classroom, and calculate the compliant floor area of each, and then divide by the total floor area of the 40 classrooms to get a percentage and compare this percentage to 75% ? Note that this option might mean that all classrooms are not individually compliant, but the underexposure of one classroom combined with the overexposure of another, will result in an equivalent compliance of the whole classrooms.

3) Can I NOT use the method of the bays for the classrooms, and calculate the compliant area of each classroom based on the Window areas, the VLT, and the range of compliance (0.15 - 0.18)? Afterwards, I'll use either option 1 or 2 asked above.

4) I have Light shelves and fins/overhangs on my windows. I understand from the discussion above that these cannot be incorporated into the prescriptive calculations. How does the LEED Reference Guidance relate to these glare control measures? Is it that I must have 75% of classrooms adequately day lit and use glare control measures on all windows of these classrooms? OR should the glare control devices be located in classrooms which are non-compliant (fall outside the range of 0.15-0.18) ?

Many thanks!