HB Window Construction Shade, no difference of peak loads


I’m trying to simulate peak cooling loads of dynamic shades and windows using LBT 1.3.0.
I’ve tried different test conditions, but the results of peak cooling loads are the same.
The component I’m using is “HB Window Construction Shade”.
The file is here.Simple Ver.gh (63.5 KB)
Please let me know what I’ve done wrong.


I think that doing an ideal air loads OS simulation may return better, I don’t think peak loads sims are going to do the same level of detail; I believe they may be a bit more granular. But I could be wrong, I took a look at the file and did some poking around.
It’s attached: I did not get to the point of runing a full E+ simulation. Likely not anything useful in it past what you have but that’s what I did to investigate.Simple Ver TF Modified.gh (87.9 KB)

What control strategy did you choose for the shades and are you sure that it is active during the Summer Design Day?

Also, interior shades really don’t have much of an effect on cooling and heating loads since the sun is already in the space by the time it hits them. Blinds and shades obviously have a big effect on glare and thermal comfort. But you should probably put the shades on the exterior if you want to see a significant difference in the cooling load.

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Thank you! I think you’re right. Maybe E+ cannot simulate that many details. I tried EUI, and the results are also the same.

I want to test energy performances of different types of dynamic shades and glazing, so I tried a lot of different control types and setpoints, but I got the same results. The shades are on the exterior. I’m not sure which part went wrong.

have you checked the design day w/m^2 per each surface explicitly by timestep to ensure that the ‘controlling params’ are actually being activated? 2000 seems to me like alot for a single timestep from what I saw, @chris would obvs better know if I’m off path here but that’s my thought process at the moment.
I am not explicitly familiar with the control params for shading in this context: not somthing I’ve done in this interface to be transparent

I have checked them and there is still no difference among the three test conditions. I’m not quite sure whether the control params are activated. I did put different “control types” and “setpoints”.

I see a pretty significant difference with a simple sample that I created.

Here it is without shade:

Here it is with shade:

You probably just need to set up your model correctly. Here’s the file that is working for me:
shoe_box_peak_loads_window_shade.gh (71.2 KB)

Thank you, @chris ! The problem might be that I used “Apply Shade Construction” instead of “Apply Window Construction”. However, when I used “Glass Material” instead of “Shade Material” for “Window Construction Shade”, the peak loads work fine, but “Model to OSM” got errors. I cannot get EUI or thermal comfort results of dynamic glass. shoe_box_EUI_EC.gh (129.1 KB)

I used your workflow, and I’m not sure what’s the problem.

Hi @wishxx ,

There was a bug in the LBT 1.3 stable release related to the use of Window Construction Shade to model switchable window constructions (that use glazing materials for shades). The bug has been fixed in the development version of the plugin as noted here:

So you can get the fix on your end by running the LB Versioner, restarting Rhino/Grasshopper, and then running the LB Sync Grasshopper File to sync your Grasshopper file with your installed version.

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Thank you so much! Now everything works well.