Conceptual Energy Analysis in Revit (8 of 8)


Well, this is it.  The cone of silence is coming off.  Now, my mother always said, if you can’t say something nice, then don’t say anything at all.  In addition, I have always felt that “the truth” is no excuse for hurting someone’s feelings.  So with those two things in mind, I will make the following entry.

It has been a number of months since my last post.  In that time I have been learnin’ me some stuff.  I have been learnin’ that there are some super smart people in my company that know a whole lot about energy modeling and energy analysis.  I have also learnt that there are standards, protocols and procedures that are industry wide in the area of energy modeling.  So with my newly found learnin’, I have a couple comments on the Revit Conceptual Analysis tool.


First, let’s talk about zones.  The automatic zoning does not follow standards.  I am not going to quote chapter and verse of where the discrepancies are, but I do know that this is right..


and this is not right.


The automatic perimeter zones do not stay at the corners of the geometry as is dictated by industry practices.

Other Stuff

There are some other issues that need to be addressed before this is going to be a good automated tool.  I don’t really feel like listing them all.  Suffice to say that before embarking on any preliminary energy analysis using the CEA tool, be sure you are aware of the energy modeling industry standards for modeling and setting up zones.  Some good references are ANSI/ASHRAE/IESNA Standard 90.1-2007 (I-P Edition) Page 179 and Commercial Buildings Energy Modeling Guidelines and Procedures, RESNET Publication 2010-001.  This is not all inclusive, but it is a good place to start.

In Conclusion

This has been a fun series.  I have learned me a ton of stuff…my head hurts ‘cause it’s so full.  I think I will continue to write on Revit CEA, now that 2012 is out.  I will probably write some on Ecotect, Green Building Studio and gbXML. 

Also, I will be attending the AIA Convention in a couple weeks in New Orleans.  I am planning to blog about all of the classes and events I will be attending.  Lots of stuff about AIA TAP and BIM and sustainability.  So come back and check me out soon. 


  1. Hi Darren,
    Thanks for the great series. We realize that auto-zoning is lacking - we'd love to hear more about your list of needed improvements for CEA.
    Lillian.Smith at Autodesk.com

  2. i am using revit mep for HVAC plant design...while doing energy analysis of one the project ...i stuck at problem. i have to assign 10 peoples and 2000watt light load & 25K watt equipment load for my mass model..how do i do that?????
    i tried by selecting building type dialog in energy analysis tab but wont able customize its parameter as per my requirement..even changing its parameter from heating & cooling load dialog in space type but that also wont work in CEA analysis..
    what to do now???