Module 3 - Points to Ponder

Why is it important to accurately model the land features of your project site with a toposurface?

• What aspects of a building design are most affected by the terrain features?
• The material that the basement walls are constructed of. If the basement is being built below the ground, it needs thicker walls that would prevent water from coming in.
• Whether or not the building needs to be supported by stilts on sloping terrain.
• If water pooling is going to be an issue.
• Terrain features can decide what kind of foundation is needed for the building. On flat terrain, a pad foundation might be best while on steep sloping terrain, spread footings might be necessary for the greater outward loads. Modeling the land features would be very important in justifying the foundation type as without it, it would be hard to visualize why one foundation would be better than the other.

When designing a project...

• Ideally, the building should adapt to the terrain. While terrain can be changed, whether it be leveled or infilled, this could still affect how the building withstands the elements in the future. If the building is built on a slope, even a level pad is created for the building on the slope, possible landslides or soil liquefaction in future storms could result in the building becoming unstable. If instead the building is built to adapt to the terrain, it could be designed to better withstand how the terrain would affect the building and could be built with the proper structural elements to prevent possible damage.

Why do stairs follow specific proportions with a set relationship between the tread length and riser height?

• Stairs follow specific proportions as it could be a tripping hazard if every stair had different dimensions. Most people walk up stairs without looking down, so if all stairs have the same relationship between tread length and riser height, then it should feel normal going up the stairs. Without the set relationship, walking up stairs would be challenging and very awkward.
• How can building modeling help prevent the mistakes that often occur when designing and installing stairs?
• Modeling stairs shows exactly how many treads are needed on the stairs to maintain the correct rise to length relationship without the need to do any manual calculations, which greatly helps to prevent any errors.