Thursday, April 20, 2017

Autodesk Insight 360 - Walls; Part 1

Autodesk Insight 360 is a powerful energy modeling tool in conjunction with a Revit model. To help realize it's full potential, I thought I would offer up a series of short posts which focus on specific elements of Revit, Insight and energy modeling. You may be surprised at how simple, yet powerful, this feature set can be!

I plan on writing a few short posts to cover just walls in the content of energy modeling. I will start with these three topics:
  • Massing
  • Revit walls
  • Window to Wall Ratio (WWR)
For this post, I want to highlight how Revit defines exterior wall construction, from mass elements, when generating the Energy Analytical Model (EAM).

We can perform an energy analysis against simple Revit massing. In the images below I created a super simple mass. This mass extends below level 1 to define a basement area. I selected the mass and used the Mass Floors button on the Ribbon to specify Basement and Level 1 for this specific element.
  • FYI: If I did not specify Mass Floors, the entire element would be seen as a shade surface. This is helpful when representing adjacent buildings.
Before we get to Insight we need to create an EAM in Revit. There is a lot of cool stuff happening here. For now, given our "wall" focus, we will notice from the next two images that the EAM understands above grade and below grade walls. In the next post we will see it even understands parapet walls when using Revit elements (i.e. not massing).

EAM with an exterior wall selected

EAM with below grade wall selected
The thermal properties of a wall are defined in the Energy Settings dialog. In the Other Options sub-dialog, there are three successive options; Conceptual Types, Schematic Types and Detailed Elements. By default, Revit uses the Conceptual Types settings as we will see...

The image below shows an extreme example of no insulation so it is super clear what is happening when we get into Insight. Notice, this is set in Conceptual Types.

Exterior walls set to uninsulated in Conceptual Types
When we get to Insight we see the "BIM setting" (triangle symbol) for wall construction is aligned with the uninsulated end of the spectrum per our selection within Revit.
  • FYI: I used to think the "BIM setting" replaced the input it aligned with on the Cost Range slider, but as you can see below it is just positioned along side it; notice Uninsulated is still a separate option even though it is the same value as the "BIM setting".

Wall construction result in Insight

If we apply an override in Schematic Types, this takes precedent over the Conceptual Types setting... but just for the categories selected. In the example below, only walls are overriding the Conceptual Types settings. Here I go towards the other end of the spectrum with an R38 wall construction.

Wall value override selected in Schematic Types
Back in Insight we see the "BIM Setting" has moved accordingly.

Wall construction result in Insight
The Conceptual Types options are somewhat limited, Schematic Types have a lot more options, and when we get to using Revit materials to define thermal properties there is no limit to the number of options we could have (as we will see in a later post).

I was working with one of our architects this week and she noticed that Schematic Types even has a Straw Bale option as seen in the image below!

Straw bale wall construction option within Schematic Types
The great thing about Insight is we can dynamically modify these inputs apart from the Revit model. However, this information is helpful to understand so you can set some baseline inputs, e.g. based on your state's energy code or ASHRAE 90.1, within your template. And, as the project progresses and decisions are made, those decisions can be captured within the BIM.

Stay tuned for more...


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