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Set Skylight to RoofCeiling Ratio?

asked 2015-04-06 17:19:26 -0500

updated 2017-08-05 13:24:10 -0500

I'm working on a warehouse project that is going to use dayligth as a ECM and 12% of the roof ceiling is going to be skylight. I would like to know if theres a plugin or an option to model the skylight's pretty much like the "Set Window to Wall Ratio Plugin" or if theres another option instead of doing one by one? as you can see I have a long way to go.

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I need to create around 144 skylights due to the curve of the roof ceiling and I always avoid copy anything when it comes to sketch up in my expirience I end up with a lot of errors.

image descriptionC:\fakepath\Captura 2.PNG

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answered 2015-04-06 21:05:18 -0500

If you want to make a measure, there is are a few methods in the API that might work for you. Building::generateSkylightPattern generates a grid that covers the entire building's bounding box. The applySkylightPattern projects that pattern onto all the roof surfaces and creates sub surfaces for the skylights. If you don't like the grid that generateSkylightPattern gives you, you can make your own. This unit test shows how it all works.

Otherwise, you can draw loose geometry in SketchUp and then use the project loose geometry tool to project it onto your model.

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@Julian Nino here's an enhanced version of the set WWR measure that might be helpful. It allows you to Add Remove Or Replace Windows By Facade.

MatthewSteen's avatar MatthewSteen  ( 2015-04-06 21:14:34 -0500 )edit

The methods @macumber mentioned are exercised in the K12 and office AEDG fenestration measures. They will be the top two search results on the link above. The current pattern method lets you set ratio and skylight size, and then spacing is determined to meet those requirements. It results in a grid of skylights, and works on flat or sloped ceilings, and also non-rectangular surfaces. This is powered by @macumber-magic.

The comment below shows some of the code from one of the AEDG measures.

David Goldwasser's avatar David Goldwasser  ( 2015-04-06 22:49:59 -0500 )edit

making vector

      # making vector
      spaces =
      spaces << space

      # making pattern
      ratio = daylightFenestrationRulesHash["#{climateZoneNumber} Skylight"]["dFRmin"]
      pattern = OpenStudio::Model::generateSkylightPattern(spaces,spaces[0].directionofRelativeNorth,ratio, skylightSize, skylightSize) # ratio, x value, y value

      # applying skylight pattern
      skylights = OpenStudio::Model::applySkylightPattern(pattern, spaces,
David Goldwasser's avatar David Goldwasser  ( 2015-04-06 22:50:49 -0500 )edit

answered 2015-04-06 20:01:17 -0500

@Julian Nino, do you mean is there an OpenStudio measure Set_Skylight_To_Roof_Ratio similar to the Set_Window_To_WAll_Ratio_By_Facade measure? ( There is not that I know of. At least not in the BCL. And the measure will not work on the roof as is. However, you could try to use it as a template to create a Set_Skylight_To_Roof_Ratio measure yourself. Shouldn't be very hard if you don't care about exact skylight geometry within a surface and could be fun!

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I wonder if the built in setWindowToWallRatio method in that measure will work on non-wall surfaces since it takes a double heightOffsetFromFloor? Might have to try it.

MatthewSteen's avatar MatthewSteen  ( 2015-04-06 20:11:28 -0500 )edit

MattewSteen, the set window to wall ratio measure on BCL has specific code to limit to walls surfaces with exterior boundary condition, but you could set it to run on a wall. That may be fine on A-frame style sloped roof, but I would expect odd behavior on a flat roof.

David Goldwasser's avatar David Goldwasser  ( 2015-04-06 23:18:50 -0500 )edit

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Asked: 2015-04-06 17:19:26 -0500

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Last updated: Apr 06 '15