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Revit (gbxml) to Openstudio

asked 2017-12-01 08:27:53 -0600

Arghavan.A gravatar image

updated 2017-12-01 08:45:53 -0600

I have a doubt, so, sorry if I am writing this on the wrong place or someone has asked this before!

I am importing my model from Revit to OpenStudio or let's say Euclid through gbXML import. I notice that while some parts of the geometry of model is being imported correctly, the floor dimensions are nor exported!!!

(In the picture below) The wall height is 2.7 m in Revit model, the wall height in OS is 2.84, meaning that wall height (2.7 m)+roof thickness (0.14 m) . Does this means that OS has interpreted that space height for calculation is 2.84 m (yellow)?

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Additionally, I can see that in my model, the floor is not imported! No thickness, no nothing! the thickness should be around 1 meter as marked by magenta question mark in first picture. image description

So, my first question is that why I am facing these situation and are they normal or am I not entering correct setting or something?

But my most important question is that when I want to import to gbXML from Revit, from "Use Room/Space Volumes", following window pops up. Is the green space the space that is going to be analysed for thermal energy?? and if so, why roof is considered inside the space in OS but not thickness?

image description

I also face this warning: image description

link to Revit and gbXML:

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answered 2017-12-03 04:49:16 -0600

Dinosaver gravatar image

updated 2017-12-03 04:51:17 -0600

With all my respect, you must read Revit help first, then watch some videos from Autodesk University or whatever to understand how gbXML export works (or doesn't work) in Revit.

  1. You always check your model in Revit in a "Detailed" tab with "Analytical surfaces" option enabled. This will explicitly show you what Revit is going to export and how. Pay attention to warnings and air gaps.
  2. If I am not mistaking, assigning a position of a roof to its upper surface is a gbXML 0.37 feature. The same for floors. So yes, to get a closed volume you will see walls slightly extended. Moreover, the position of walls is their center line, so be aware how your room area and volumes are computed and how you align floors and roofs to walls - sometimes you will see shading surfaces or air gaps on their perimeter.

  3. Your floor is not exported because it is too thick - check the "Sliver space tolerance" parameter. It is created for another purpose, but also affects on surfaces thicker than its value. So, in your case it must be more than 1100 mm. At the same time it means that in your model there must not be spaces of size less than this (e.g.risers) - they will not be exported.

  4. Cannot say anything about your last error - actually from my experience it either means that a surface has wrong classification (e.g. interior instead of exterior) or there are pieces of walls which are interpreted as interior walls - these are not translated by OS, that's correct. This happens mostly when in your Revit model walls are not aligned and connected by their center lines.
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@Dinosaver Thank you so much!!! I'll check these points with my model and get back to you :)

Arghavan.A gravatar imageArghavan.A ( 2017-12-03 06:13:00 -0600 )edit

@Dinosaver Do you think that these changes that you mentioned to correct my model also affects the model exported to IFC?

Arghavan.A gravatar imageArghavan.A ( 2017-12-06 08:41:52 -0600 )edit

In terms of space boundaries - yes.

Dinosaver gravatar imageDinosaver ( 2017-12-06 08:43:58 -0600 )edit

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Asked: 2017-12-01 08:27:53 -0600

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Last updated: Dec 03