Thesis Excerpt: Comparing Site Built vs. Prefab/Modular Construction

First, an issue which I mentioned in chapter 5 involved comparing site built construction with pre-fabricated and/or modular construction to offset hard costs and increase housing affordability.  In the case of the AFI, these strategies have been compared during the bidding phase for a single project which utilized a non-BIM workflow and it was determined (at the time) that pre-fabrication or modular construction was not economically feasible.  A potential area of research could be to investigate the impact a BIM workflow would have on a pre-fabricated or modular design in terms of overall construction costs.  It might be determined that the only way to make pre-fabrication or modular construction affordable (BIM or not), is to increase the scale of production.  A related and possible continuation of this research topic would be to explore the benefits of BIM versus CAD workflows for a multi-unit development.  This concept has been envisioned as a possible strategy for scaling-up the AFI, but it has yet to be tested as a real project.  Several local architects and contractors I interviewed in Austin all agreed that a multi-unit development would bring down costs, but it is unclear by how much and if BIM would have a significant impact if any.  Aside from hard costs, it could be theorized that at least soft costs could be reduced by using BIM on a multi-unit development by reducing the time needed to complete construction documents and make corrections/changes.  Overall, this research would require testing BIM and non-BIM workflow strategies for single housing developments and multiple housing developments over entire project timelines.

Source:  Dowhower, Justin Firuz.  Adapting Building Information Modeling (BIM) for Affordable & Sustainable Housing:  Chapter 7:  Future Research.  Austin, TX:  The University of Texas at Austin, 2010.