One of the key benefits of IES VE tools is our collaboration with Autodesk, Google and Graphisoft which allows designers and architects to use their BIM/CAD model to start performing analysis at the very early design stage. It can simplify the process of recreating the model from scratch, as you would have had to do in the traditional way.
Through this, many architects are starting to realize that building performance analysis is not only for engineers, and that by working holistically from conceptual stage, the project can achieve much better efficiencies than when analysis is left till later phases of the project.
In traditional building performance modeling, the modeler uses information from drawings, photos, etc. to construct a model within simulation software from scratch. Misinterpreting the information from CAD to building performance model is common, and in some cases important geometry might be missing from the information provided or left out of the model by accident.
As BIM becomes increasingly popular in the architecture industry and more connections to analysis tools appear and strengthen, architects can start performing analysis on different design options, including climate understanding, building orientation, massing during conceptual stages, and as the design develops, analysis such as daylight assessment, water review, heating/cooling loads, renewable use, etc. IES has a direct plug-in for both Autodesk Revit and Google SketchUp, as well as direct connectivity to Graphisoft ArchiCAD.
One important thing to note is that there are some fundamental differences between an energy model and an architectural model used to generate construction documents. Schema’s such as gbXML (www.gbxml.org) are used to streamline the data flow between BIM platforms and analysis tools, so users should have an understanding of how this works and what will translate, and what will not.
A model that is very heavy in details will affect the computation time of the simulation. One of the things I like to do whenever I start running simulation is to spend 15-30 minutes cleaning up any elements that are not necessary for energy analysis (of course doing a “Save As” on your existing model first). I know a lot of architects are probably saying if we have a direct plug-in, why do I want to waste all this time cleaning up the model? Isn’t that the reason why we want to use the plug-in?
Spending a little extra time cleaning up a model before running a simulation, will reduce the file size and run time; if you are doing a few simulations it’s definitely worth the time. The IES VE will still run the simulation if you don’t clean up the model, but it will go through every element within it trying to figure out what needs to be included and what doesn’t, which can take a lot of time. Plus, the more detail you have in the model, the more risk of inaccuracy during translation. If you want to understand more about model translation, visit our website for whitepapers on both SketchUp and Revit to IES: http://www.iesve.com/Learning/IES-Whitepapers
