What are the principal advantages of using a single building information model of the existing conditions as the foundation for modeling proposed additions or renovations?
- Why not create a separate model for the new proposed design?
Using a single building information model of the existing conditions provides a consistent and accurate foundation for any proposed extensions or renovations. Working in one model ensures that all designers reference the same shapes, levels, grids, and building systems. This reduces error and improves overall coordination. It also make it easier to model difference between the old construction and the new construction plan. Creating a separate model for the new design introduces unnecessary complexity as multiple files must be managed and kept in sync. Additionally, even small inconsistences between the files in terms of dimensions or alignment can lead to major coordination problems down the line of construction.
What sort of complexities are introduced when you construct a building complex in phases?
- What happens at the interfaces between the buildings as the phases advance?
- How can you plan and prepare for these complexities as your create your initial building model?
Constructing a building complex in phases introduces challenges at the interfaces between phases where structural, architectural, and MEP systems must align precisely. Floors, gridlines, offset measurements must match. In terms of further along the construction line, envelope edges must be waterproofed. Mechanical and electrical systems require temporary routing until later phases are built. As phases advance, each new section has to connect cleanly to the previous one without disrupting and totally destroying the completed work. To prepare for these complexities, the initial building model should clearly define interface zones, establish fixed levels and gridlines, and include placeholders for future structural and MEP connections. Therefore, modeling with phased worksets can help to document temporary conditions and can ensure each phase is integrated smoothly throughout the overall project construction.
What are the principal advantages of using a single building information model of the existing conditions as the foundation for modeling several proposed design alternatives for a portion of the building?
- Why not create a separate model for each of the design alternatives?
In your project, which features of the proposed design did you choose to model as design alternatives?
- Why did you choose these building features? And what were the biggest challenges in modeling them as the design alternatives?