Analytical spaces

[jovita.marcinkeviciute]

Hello, I have  a problem with analytical spaces. I do not know why it show me few or more times same room name? (added screeenshot)

Thank you

[robert.klempau]

Hello @jovita.marcinkeviciute,

please check this Knowledge base item:

Create the Energy Model 

This will help you to understand how energy models work within Revit.

[garrettducatC9DPE]

When architects model walls, ceilings, floors, and other building elements they can be "room bounding."

The error is most likely a floor or a ceiling that is cutting the space into multiple spaces. Use "highlight in model" in a 3D view to see where the duplicate spaces are happening.

[RIPENG]

Revit Version: 2021.1.3

I also experienced unexpected analytical spaces/surfaces in Revit's Energy Analytical Model while working through a simple shoebox building geometry example to evaluate Energy Analytical Model performance for production use.

Mode = Use Conceptual Masses and Building Elements

Reference = Energy Settings

To see if I could provoke different results I played around with 'Analytical Space Resolution'. UI path to 'Analytical Space Resolution': Analyze >> Energy Optimization >> Energy Settings >> Energy Analytical Model >> Analytical Space Resolution.

For my simple shoebox  example decreasing the 'Analytical Space Resolution' by increasing the setting from 4' 0" to 4' 6" resolved the unexpected spaces. Please see the attached PDF for details.

Mode = Building Elements

Reference 1 = Energy Settings Video Transcript

"The Mode setting is the most important setting, it controls what geometry will be used for analysis. If your model does not contain conceptual masses, set Mode to Use Building Elements. The other 2 modes are used when you have conceptual mass elements modeled and want to include them in the energy analysis."

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Reference 2 = Energy Settings - Mode

"Revit offers 3 modes for creating the energy model from the architectural model. For all cases, however, you should use the default mode: Use Conceptual Masses and Building Elements. "

Following the guidance of Reference 1 cleared up the Unexpected Analytical Spaces / Analytical Space Resolution dependency for my simple shoebox example. Please see the attached PDF for details.

Recommendations

1. Users - Follow Reference 1 guidance and disregard Reference 2 guidance.

2. Autodesk - Revise guidance and/or Revit mode handling.

Best wishes,

Jake Staub

[iainsavage]

Autodesk recommend using the Use Conceptual Masses and Building Elements settings.

If there are Building Elements then any Conceptual Masses should then be ignored when the Energy Model is created.

For Building Elements It then automatically applies a heirarchy  (from top down) as follows:

• if there are are architectural elements in the model or link and the Detailed Elements box is checked then the properties of those architectural elements will be used
• if Detailed Elements is not checked or there are no architectural elements in the model then the building Schematic Types will be used if the override box is checked.
• 
• if Detailed Elements is not checked or there are no architectural elements or Schematic Types are not overridden then the Conceptual Types will be used. (“Conceptual types determine the thermal properties used for energy analysis when thermal properties are not otherwise defined using schematic types or detailed elements.

  These settings relate to the energy model created from both conceptual masses and building elements when using the recommended mode Use Conceptual Masses and Building Elements.”)

[RIPENG]

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@iainsavage wrote:

Autodesk recommend using the Use Conceptual Masses and Building Elements settings.

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The recommendation above seems inappropriate for Revit 2021 in cases where:

1. Only Building Elements are present in the Revit environment,

2. Users desire consistency between Building Elements and Analytical Spaces.

Whether or not consistency is required between Building Elements and Analytical Spaces to produce accurate energy modelling results is a different question. However, consistency is important for human in the loop validation/verification of Energy Analytical Models prior to simulation. Inconsistency is what caught the attention of both the OP and myself.

In terms of numerical flow, consistency is also critical to productive data transport from analysis tools back to Revit for design purposes.

-Jake