CIE overcast sky

[Arun Shaju]

Hello

Is there any way to do shading analysis in SunCast having an overcast Commission International de l’Eclairage (CIE) sky. I dont see this sky type in the options

Thanxxx

[david-ies]

Hello,

No that is not possible in SunCast.

Suncast assumes a clear sky and produces an input file for Apache which has data for which surfaces on the outside of the building are shaded and which internal surfaces receive direct sunlight. Apache then reads the solar data input file from SunCast and uses it to modify the beam component of solar radiation (from the hourly averaged weather file), and when the beam enters the building through glazing, to assign it to interior surfaces.

Oh, also... SunCast (If requested) when calculating the shading file will also contain diffuse shading factors indicating, for each exposed surface of the building, the degree of shading from the sky vault.

You can utilise a CIE sky (along with the clear and sunny skies) in the Radiance illuminance sensor calculations which Apache can use.

Hope that helps a bit.

David.

[Arun Shaju]

Hello David,

Thanks for the reply. I'm actually trying to do a shading analysis for obtaining GSAS credits. For compliance with GSAS we need to find the shading on adjacent properties with CIE sky. The standard specifies that a CIE sky need to be used while doing the analysis.

Regards
Arun

[PCully]

Hi Arun,

I think you would be better looking at using Radiance for this type of analysis which will let you choose the CIE sky and then you can look at impact of the building on adjacent buildings in a form which will provide you with the credit compliance assessment (I believe).

Phil