Which types of structural framing systems and materials are most commonly used in the US for residences? For office buildings?
For smaller residential buildings that usually have up to 4 levels, timber and wood is typically used. Because they are smaller buildings, they do not need as stiff of materials as larger skyscrapers to other structures of that size. Office buildings are typically much taller and larger in plan size, therefore requiring either steel or reinforced concrete to account for the larger weight and loads that it will take. It is not common to use wood for these types of structures, but mass timber is growing more popular in the US and could be used.
How do you think design coordination was done before we started using digital models?
Before digital models of buildings, all drawings were done by hand by each of the engineers. It seems that one team, likely the architect, would have to start drafting their ideas first and then hand off the physical drawing to the structural engineers. From there, the structural engineers can design the structural system and then pass it back to the architects. In this case, teams cannot work on the project simultaneously and have to wait for updates, which online coordination speeds up immensely. It is also easier to check for clashes with the digital model as the computer can run the clash for you, instead of checking by hand.
At what point in the project development process should design coordination start?
Design coordination should start as early as possible, right as the structure is starting to be conceptualized. When the engineers and architects start working together in the beginning of the ideation process, major structural elements can be estimated and located which will help the architect make changes as needed. This also helps the MEP team start working on electric wire and plumbing runs, and lets them update as needed. Therefore, over a larger time of the project, updates from all subteams can be made and a full draft can be presented to the client as needed.