Why is it important to accurately model the land features of your project site with a toposurface?
Accurately modeling the land features of your project site using a toposurface is important for the accuracy of your building model! The toposurface represents the real-world terrain, which can heavily influence the overall design of your building depending on whether it’s flat, slanted/steep, hilly, mountainous, dense with trees, etc. Building facades may look different depending on whether you're building on a flat surface or a hill, which then would mean you need to build into it or extrude concrete to build on a level surface. The material you're building on top of might also dictate your design. For instance, building on limestone that 6 inches below the surface in Florida is much different from building on the bedrock in the Bay Area.
When designing a project...
Depending on the location, purpose, budget, etc. of the project, deciding on whether to adapt the building into the terrain or alter it to fit the building’s need is ultimately a design choice that needs to be made by the project stakeholders. In “sustainable” design, you often see buildings integrating with their surrounding environment, sometimes in the most literal of terms (i.e Library in the Earth in Chiba, Japan), to align with the sustainability goals of environmental consciousness. Other times, the terrain will not allow you to build in the way that you would conceptually like considering budget, expertise, etc., so changing the terrain for an easier construction might have to happen (i.e. pouring concrete to level a hill, raising a house on stilts, etc.)
Why do stairs follow specific proportions with a set relationship between the tread length and riser height?
Stairs follow specific proportions for the tread length and riser height to comply with fire safety and ADA standards, as well as provide comfort and ease of use based on human anatomy. Having standardized stair proportions allows for greater ease of modeling, constructing, and installing, since everyone can relatively be on the same page as so how the construction needs to be. Modeling stairs digitally allows you to plan for its installation into a building, which can help to identify mistakes in design (sizing, fit, number of risers needed) before they are executed.