Automatic window shade inclination to block the direct sunlight

Hallo dear community,

I need a clarification on whether is possible to made this type of analysis:

Is there a method that automatically manages the inclination of the shades, to block the direct sunlight in a annual daylight analysis? or a metod to find the right shade inclination for each HOY to avoid the direct sunlight?

Any existing example to study the procedure?

Thanks and best regards

Hi, @LaFleur - the short answer is yes. The solution will depend on if you are trying to model them as dynamic blinds or find an optimal angle for the whole year and use that. In both cases, it is possible.

Dear mostapha thanks for the answer.

the venetian blinds that will be mounted have an automatic cut-off system, therefore I would need that the inclination of the blind in the simulation change autonomously to control the sunlight and see the result inside the room, without predefining a blind angle. Is this possible? Any advice on which component is appropriate to use? or if an example has already been given?

I have one more question. For another Analysis I need to control a blind shade (closed or open, based on how many W/m² the facade receives) for a annual daylight analysis. I saw that the HB Windows Construction component can help me with this, but I doubt if it works only for energy models or also for radiance simulation.
I can’t figure out what position the blinds are when the shade are closed. Are completely closed aka 90° or inclined by 45°?

Thanks in advance for the help

The angle is as it comes from the blinds material component. The default being 45°.

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Thanks dear Abraham, now is clear but my doubt now if the component WindowsConstrShd work for Radiance simulation, or only for E+ analysis.

Any advice about this?

Thanks and have a good day

Hi @LaFleur ,

It works ONLY for E+ simulations. For Radiance you need to model real shades. Try the HB_LouverShades component. It will give you geometries that Radiance understands.

Can’t help you with the other question … though will be happy to see the solution.

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Dear @mostapha, I found myself facing this issue and make me strange not to find a component that calculate the cut-off angle of a slat for blocking the direct sunlight. Or simple didn’t find it?

@AbrahamYezioro I would to ask: would be correct to analyse Daylight, taking in consideration blinds/louvers, etc only with a 2-Phase Metod?


Isn’t is always equal to the altitude of the sun whenever the blind spacing and the blind depth are the same?

It’s possible to do this but you’d be modeling each of the blind states with detailed geometries, which can be pretty time consuming. I imagine that most Radiance modelers would try to account for this with BSDF files to represent the venetian blinds. I think we are close to releasing a three-phase recipe, though @mikkel knows more about this than I right now.

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Dear Chris, I don’t want to be wrong, but I don’t think so, unless I misunderstood your answer.
I attached a help for the cut-off angle equation

I am little strange that this function is not already present in a component, also because it is a type of analysis that is increasingly requested and is included in several regulations.

Thanks for the info.

Thank you always for your availability
Bestia regards