Dear All,
I have difficulties to define window groups for internal shading control when carrying out Option 1 (sDA) daylight simulation for a core and shell office building.
1. What is the best practice for this? In case of a hypothetical, rectangular floor plan with the core in the middle, do I need to create 4 window goups (by orientation) and assign the relevant grid area to each window group by connecting the corners of the core and facade? (resulting in 4 trapeze shaped analysis grid)
2. If a facade is long (i.e. 40 meters), do I need to further divide the windows on it into smaller window groups? (i.e. 1 group by 6 meters) – and so further dividing the grid area for a more appropriate shading control
3. Do I overcomplicate this shading control issue? I did not find any case study for core and shell projects OR any corner offices that would raise the same question as question nr. 1.
Thank you for your advices, unfortunately I could not attach a drawing to support my quetions.
Daniel Glaser
PrincipalLightStanza
LEEDuser Expert
18 thumbs up
July 26, 2017 - 7:59 am
Hi Diana,
Those are astute questions about how to model blinds for an accurate sDA score.
1. Yes, you will need 4 window groups since each side of your facade has a different “view” of the sun. 4 trapezoidal grid spaces on the interior will model blinds more accurately than a single one because of the 2% rule (measuring for when the blinds will be closed). The blind control for 1 large space will be harder to trigger.
2. Unless you are using different blinds/shades or have different exterior conditions, LM-83 does not have provisions for dividing your facade further (e.g. you should keep your long facade as a single window group).
3. These are very good questions and get at fundamental aspects of the sDA calculation. We have written about this in more detail at:
http://lightstanza.com/news.html#filter=.sdaSeries
Specifically you may find the following sections of interest:
SDA 4: Step 1. Blinds Operations
SDA 5: Blinds Operations Examples
Diana Apro
ConsultantABUD Mernokiroda Kft.
July 27, 2017 - 3:20 am
Thank you Daniel for your feedback, it was very useful indeed!