Forum discussion
HI,
when using LEED – Daylight and Quality Views Calculator, we have seen that the sDA result of any space is always counted for the overall sDA result of the building (even if ASE results are not compliant for that space). However, in some softwares we use, when ASE criteria is not met, that space automatically does not count for sDA calculations.
We couldn't find any document that clears this issue.
How have you been dealing with this issue? Following the LEED calculator?
Regards,
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Is it possible to combine Options 1 and 2 for different spaces in the same building?
What spaces are considered regularly occupied and must be included in the calculations?
What daylight simulation software can I use for LEED compliance?
My office space will have cubicles with high partitions. Should I include those in my model?
What types of glare control are acceptable for this credit?
Do I actually need to submit the USGBC Daylight and Quality Views calculator?
Can electrochromic glazing qualify as a glare control device?
Max Krueger
Sustainability SpecialistHord Coplan Macht
5 thumbs up
August 14, 2018 - 5:11 pm
https://www.usgbc.org/leedaddenda/100002149
Ricardo Sá
Director of SustainabilityEdifícios Saudáveis Consultores (503 910 767)
86 thumbs up
August 28, 2018 - 6:43 am
Thank you Max!
We have already read this interpretation but it does not help us with our doubt: a space that only complies with one criteria (ex.: sDA) is still counted for the building overall results in compliant criteria or automatically excluded as being not compliant in both criteria?
Regards,
TODD REED
Energy Program SpecialistPA DMVA
LEEDuser Expert
890 thumbs up
August 28, 2018 - 7:40 am
What software are you using? The issue is the software you are using and not the calculator. The credit requirement is that a space must meet both sDA and ASE, so it sounds like whatever program you are using is automatically removing a space. The requirements for ASE is 10% or less of all calculation points within the project. I currently use Light Stanza which separates both sDA and ASE and creates a complete report, both overall and space by space.
Ricardo Sá
Director of SustainabilityEdifícios Saudáveis Consultores (503 910 767)
86 thumbs up
August 28, 2018 - 11:57 am
Thanks for your feedback Todd!
As far as we know, this credit is evaluated from a whole-building perspective (thresholds appear to be applicable to total regularly occupied area, not each space individually). Due to this, it is important to clarify if spaces shall be evaluated independently of each other or not.
In what relates to the LEED calculator (an official USGBC document), its calculations are considering that a space can contribute to overall building sDA even if it does not comply with ASE criteria. Please note that the update of this file is mandatory, together with LEED template.
We have used LightStanza and other softwares to perform daylight simulations. LightStanza for example, has a different approach to this issue in its reports (a space only contributes to overall building sDA if its ASE score is compliant).
Given this context, and considering that we shall not upload different results between LEED calculator and Daylight simulation reports, what do you recommend us to do? Have you got any feedback from other users regarding this issue?
Regards,
TODD REED
Energy Program SpecialistPA DMVA
LEEDuser Expert
890 thumbs up
August 28, 2018 - 1:04 pm
Are you setting your analysis grid for each room separately in Light Stanza and not using the automatically generated grid? I create an analysis grid for each space and the output report notes both the sDA and ASE for each grid in the report. I've not noticed what you are saying. But yes, it would be an issue with a report showing different results than the simulation output. I know over the years that the LEED calculators seem to always be different than the actual credit language or requirements. With that, i know of many project teams that have submitted just the output report instead of completing the calculator as long the report listed the spaces separately and the reviewer could verify the requirements were met. A good narrative is priceless in explaining to the reviewer your method or why there are differences.
Daniel Glaser
PrincipalLightStanza
LEEDuser Expert
18 thumbs up
August 28, 2018 - 7:52 pm
Hi Ricardo, Todd, Max,
As Todd noted, I believe the current LEED Daylight Calculator is in need of an update since it was published in 2014, after the 2017 interpretation Max pointed out.
In 2016 the IES has responded in a letter to the USGBC clarification on this issue:
For, example, if a space within a building results in 20.0% ASE 1000,250h or higher, dynamic facades or other acceptable active glare mitigation strategies are required for this space to maintain its compliance as a daylit space and contribute to the sDA area for credits.
Likewise in the LEED interpretation it says:
Yes, spaces with an ASE1000,250h score greater than 10.0% and less than 20.0% are acceptable with a narrative describing how the space is designed to address glare.
Therefore LightStanza only adds sDA contributions for spaces <20% ASE, unless its small <250sqft or uses an dynamic system like automated blinds or dynamic glass.
I hope the LEED Daylight Calculator is updated for 2018.
- Dan