What drives a project team's decision about floor-to-floor height?
◦ From a developer's perspective?
The developer has to take many things into consideration. First, the building has to get approved, so the floor-to-floor heights have to follow code and remain feasible to build. They’re also in charge of funding, so they might take into consideration the cost of extending floor heights, as that means more materials and therefore a higher cost.
◦ From a designer's perspective?
A designer is more concerned with the look and feel of the building. They might adjust floor heights to correct the look of the outside facade. They might also adjust floor heights to create certain double-height spaces to enhance the experience of the inhabitants or create similar opportunities.
◦ From an engineer's perspective?
An engineer is most concerned about feasibility. They are correcting floor heights given the space allotted and the infrastructure that has to fit within the space allotted to each floor. If the designer wants 10ft of open space and large spans between columns, the engineer will need more overhead space to place the thicker beams required to support that design choice.
◦ From a builder's perspective?
The builder is even more concerned with feasibility. As the one who actually needs to create the building and ensure all the “pieces” fit, they are most concerned that there is enough space for everything and that it is designed accurately.
Last week we chose a massing option based on site evidence. This week you had to fit a program inside it.
◦ Where did the program and the massing disagree, and which one gave way?
The building had to be thin enough that there would be a decent-sized courtyard in the center. This led the interior to be an awkward size that was big enough to have a double-loaded corridor, but only barely. Because of this, the rooms on one side of the hallway were forced to be very shallow and wide to get them up to the required square footage. In this case, the program gave way.
◦ What would have had to be true for you to change the massing instead of the program?
I would have changed the massing if the building were not able to support a double-loaded corridor. That was a non-negotiable for me.
◦ Which of this week's program decisions will the structural engineer and the mechanical engineer assume you got right?
They will assume I got everything right that depended on stylistic choice. So, they will assume that I got the unit type distribution correct, as that was a personal preference. They will also assume that I got the placement of my circulation correct, as it's also a personal programmatic preference.
At some point, a conceptual model has to stop being conceptual.
◦ How do you know when a proposal is resolved enough to move into Revit?
You have to have a solid satisfaction with two things: the analysis results and the stylistic elements. Re-run all of the analysis and ensure that they are spotless (or that any issues are minor enough that you can accept them). Stylistic elements are a lot harder to consider ready to move on. However, if everything is functional, efficient, and visually appealing, the model can likely move on. Minor edits can still be made, but the foundation must be solid.
◦ What is the cost of moving too early? Of moving too late?
If you move on too early, you will waste a LOT of time going back and redoing things. Both programs are meant for different stages of the design process, so using one at the wrong stage of the project is horribly inefficient. This will also just make the design more muddy and disorganized conceptually. Moving too late is also a matter of inefficiency, as certain tools in Revit are much more attuned to designing the small details that you work on later in a project than Forma. You will lose time by moving on too late and most likely jeopardize the complexity of design that Revit allows.
◦ Which parts of your Forma model do you expect to survive the handoff?
The mass of the building; the programs; and the placement of major features like the windows, doors, and balconies. However, the styles or exact composition might be altered, especially as you move into choosing materials for the building.