Sustainability Analysis
Performing building performance analysis in early design is one of the best reasons to use massing in Revit. The earlier you can get feedback about your building, the easier it is to make inexpensive changes that have a major impact on the building's performance. The tools available to you in Revit are not designed to provide highly accurate results; however, accuracy isn't necessary during schematic design. What you're looking for is the change you can achieve between iterations and for the best-performing iteration relative to your other designs.
For our energy analysis, we'll rely on Vasari, since it bundles both the solar radiation tool and the energy analysis tools in one package. Also, we'll place the mass only once, and leave both the north tower and south tower checked. That way, we have continuous surfaces for the analysis to run on.
Solar Radiation As you saw in earlier chapters, you can use the solar radiation tools with massing elements to quickly determine building form and shading strategies. The advantage a mass like this offers over a typical mass is iteration. Figure 21.22 shows an example of the overall solar exposure on the building. Since the site was so constrained, we had no ability to rotate or change the massing relative to the sun. However, we were able to use this analysis to help determine where we needed to have solar shading on the exterior of the skin. The analysis also helped inform the use of triple glazing on the elliptical glazing panels to reduce heat loss. Last, since much of the sun hitting the ellipse is coming from the sides, we used vertical shading fins to help shade the ellipse on the north tower, which does get a significant amount of solar exposure.
Green Building Studio Similarly, you can analyze masses for whole building performance. This approach is particularly useful for looking at building orientation—which wasn't an option on our constrained site—but as you can see in Figure 21.23, building orientation can have a significant impact on building performance.
FIGURE 21.23 Building energy analysis
