The assigned reading from the BIM handbook was quite informative, and I feel like it stressed how far we’ve come with modeling software in general by giving a detailed history of BIM and other parametric modeling programs. I never realized CAD drafting programs had started in the mid to late 1970s. I also had assumed that modeling programs that took into account the air and space inside of a building, rather than just creating the illusion of the shell itself, were well underway before 2007. The section I found most interesting was how the aerospace industry was the first to recognize the significance and benefits associated with using a modeling program for design work. The concept of families is also interesting, but I’m still a bit confused about how you practically define parameters in order to create the object. Overall, it was a well-organized and comprehensible article that has given me a new appreciation and understanding of the complexity of these building modeling programs…as well as their current limitations and future developments.

The second article I read (Distilling the Acoustical Model from BIM Standard Architectural, Mechanical and Structural Models - Robust Acoustical Templates, Limitations & Recommendations) analyzed the incorporation of acoustic modeling into building modeling programs, taking into account special geometry, building materials, noise generation components such as HVAC systems, and the hypothetical locations of the speaker and audiences. They introduce a new type of industry foundation class (IFC) platform that would assemble the acoustical data with the architectural data. All of the acoustical properties would be stored in a common database, and then referenced by the IFC platform. This would save the acoustician a lot of time by eliminating the need for them to separately assign building material properties and analyze the acoustics in an acoustic-only simulation program. Various sound absorption, diffusion, reflection, and transmission properties can be assigned to each building material in the BIM model. In essence, a “wall” would now carry sound properties for 5/8” gypsum, a, 3-5/8” metal stud, and a 6” CMU block wall. I could see potential here for also simulating fire resistance using a similar property assignment method. Various HVAC components would have their sound power listed (AHU fan vs Cooling Tower, etc), and the model would simulate how these sounds traveled through the building. The most interesting part of this article was when they discussed how “the listener data file can contain the area of the listening audience, any listener transfer function (such as cochlear implants), and time code data for listener locations that vary with time.” The only thing I thought was a little inconvenient was that you had to export the BIM model into the IFC platform in order to run the analyses. I guess this is similar to running HVAC models in TRNSYS, but I feel like all simulations should be done from one central model for 2 reasons: one being that this would eliminate any possibility for erroneous data transfer, and secondly so that the building model could be changed in response to any acoustical simulation.