Hi,
I'm working on an office building where the 2 first floors are an existing building with the exterior envelope left intact and the 5 floors above that is a completely new construction.
- The "new floors" are complying with the LEED daylight criteria but the lower existing floors are not. How will this be evaluated from a LEED daylight perspective? Will there be an exception made on the existing part of the building or will I have to calculate some kind of average sDA value for all floors including the existing floors?
-Generally when calculating the sDA and ASE of multiple floor office buildings, do I need to run simulations for all floors or is it enough to look at a few and argue that some floors should reasonably have have very similar results? If some floors are complying and some are not, do I summarise the total SF of complying regularly occupied floor space and divide it by the total regularly occupied floor space or would any entire floor that doesn't comply be be counted as not complying when summarising all the floor space in the entire building?
Thank you so much for any clarification
Par
Dane Sanders
PrincipalClanton Associates
68 thumbs up
April 12, 2018 - 12:18 am
Hi Huli,
If your project is registered under LEED NC, including the existing building, then you will need to include all regularly occupied spaces in the building. Spaces larger than 10,000 sqft should be divided into areas smaller than 10,000 sqft (according to IES LM-83 modeling guidance) The sDA and ASE calculations are performed on a space-by-space basis for all "regularly occupied" spaces, then compiled for the whole building (not floor-by-floor). The overall sDA score for the building is tallied by the sum of the compliant sqft, divided by the sum of total "regularly occupied" sqft. Spaces that exceed 20% ASE fail the criteria and cannot be included in the compliant sqft. For example:
Room # Room Sqft ASE Sqft sDA Compliant
Room 1 100 8% 85
Room 2 100 22% 0 (disqualified)
Room 3 100 15% 95
Room 4 100 10% 95
Total 400 275 = 69% = 2 Points
If you have repetitive spaces with the same orientation, geometry, window size, glazing spec and interior finishes, then you can submit a typical sDA and ASE calculation as the supportive model evidence.
I hope this is helpful.
huli pano
April 12, 2018 - 6:50 am
Thank you very much for that great answer and example!
One last thing. With the LI #100002149, no space is disqualified due to ASE provided that automated dynamic façade systems are installed. We have Interior automated blinds with manual override which according tot he definition complies as automated dynamic facade systems. Should I still summarise the sDA like you're doing in your example but just not disqualify any spaces despite ASE>20%?
Thank you!
TODD REED
Energy Program SpecialistPA DMVA
LEEDuser Expert
890 thumbs up
April 12, 2018 - 7:30 am
Huli,
As already noted, demonstration of credit compliance is based on the sum of all spaces and not by a floor by floor basis, unless this is a CS project where it might be nothing but the floorplate. If you review IES LM 83 and the recommended modeling parameter, buildings and other obstructions within a certain distance of the project should be also be part of the model. Where in LEEDv3, a model could be stand alone, even though not good daylighting sim practice. So if your building is located in an urban environment with adjacent buildings of different heights, just simulating one similar floor and extrapolating the results may not be correct. You could have a taller building on the east, same size on the west, and smaller on the south. The effects of daylighting on each floor and orientation would be quite different requiring a simulation of all floors to truly demonstrate compliance. If the building is stand alone in some baren industrial park, then simulating one and extrapolating the data would be fine.
Dane Sanders
PrincipalClanton Associates
68 thumbs up
April 12, 2018 - 11:26 am
If you have automated dynamic facade system, then you can claim the ASE exemption and count that space in your sDA summary.