Option 3 requirements

There are no specific times to take measurements for LEED. If taking measurements to determine daylight performance, i would look at multiple times of the year, different sky conditions, and times of day. I would also take exterior readings during the interior readings.

Todd, this would be extremely expensive measurement + it will slow down the post-construction process and the overall final contruction review submission. Shouldn't it rather be March 21st or September 21st as listed in Option 1 of this credit? How do we proceed with daylight fluctuations (clear vs. overcast sky) during the measurement day? There is a lack of technical details on this option 3 in the Reference Manual. Thanks in advance, Petr

Petr, I listed what i would do to determine daylight performance, not so much as to what should be done to just document option 3. If the only concern is documentation, then i would suggest that you do it at noon, under clear sky conditions as close to the equinox as possible. As far as to handle the fluctuation in sky conditions, watch the weather forecast and and pick a day when it will be clear. Daylight is always fluctuating and these are the issues that must be addressed using measurements. The next version of LEED will require you to take measurements at two different times of the year. If you want to determine performance then the placement of sensors throughtout the spaces over a period of time would be recommended.