Cheryl Mulor - Module 7

Step 1 - Generative Design Framework

I decided to consider the three pillars of sustainability as the 3 key design considerations for my generative design study, as they offer very interesting trade offs to many designers, developers and builders today often run into. The building in consideration will be two simple cuboid buildings generated from varying height, length and width values.

Enviromental sustainability
  • Design Variables
    • Base width of building
    • Base lenghth of building
    • Height of building
    • Materials (steel, vs timber vs concrete) - embodied carbon per sf?
    • Distance to suppliers
    • Window to wall ratio (WWR) (natural lighting)
  • Evaluators
    • Embodied carbon given material + surface area + transportation distances
    • Solar generation potential given roof area
    • Building energy consumption / Operational carbon
  • Most Important Tradeoffs to Consider
    • Embodied carbon vs solar generation potential. A larger roof surafce area would lead to higher generation potential but would also lead to higher material usage and higher embodied carbon as a result
    • WWR vs Energy consumption: Higher WWR might be good for reducing the building lighting load but might also increase energy consumption due to higher cooling loads.
    • Embodied carbon vs material cost/construction cost: A lower carbon material could be more expensive than a higher carbon material
Economic sustainability
  • Design Variables
    • Base width of buildings
    • Base lenghth of buildings
    • Height of buildings
    • Materials (steel, vs timber vs concrete) - Cost per sf?
  • Evaluators
    • Building construction cost (material - exclude labor for now)
    • Building energy consumption / Operational cost
    • Solar generation potential
  • Most Important Tradeoffs to Consider
    • Construction cost vs operational cost
    • Construction cost vs solar generation potential
    • Construction cost vs embodied carbon
Social sustainability
  • Design Variables
    • WWR
    • Base width of building
    • Base lenghth of building
    • Height of building
    • Distance to suppliers (empowering local suppliers)
  • Evaluators
    • Available floor area per person
    • Views
    • Natural lighting
    • Amount of material purchased from local suppliers
    • Building cost
  • Most Important Tradeoffs to Consider
    • Available floor area vs building cost (or rental cost even). Want to maximize available floor area but minimize building cost (and in turn rental cost for occupants)
    • building cost vs amount of material purchased from local suppliers (it might be expensive to buy materials closer than further away)
    • Embodied carbon vs Available floor area. Want to maximize floor area but minimize embodied carbon.
    • Amount of glazing vs building cost (energy consumption)

Step 2 - Generative Design Study

In order to keep it simple in terms of inputs that would be required as well as evaluators to be considered, I decided to conduct a generative study of the second design decision of Economic sustainability of the building while also considering one environmental design evaluator (embodied carbon).

  • Objective: What ideal dimensions for each of my buildings (made from different materials) should be used in order to minimize building construction cost, operational cost and embodied carbon, while maximizing the solar generational potential and the available floor space. The operational cost and solar generation potential are directly proportional to each other.
  • Model: The model will consist of two buildings, one made of steel and the other made of timber. Both buildings will have varying height, radius of circles used to create the polygons for the cross sections. They will also each have maximum allowable heights that they can be built upto with the steel building having a higher one because of its strength compared to wood. The study will aim to minimize the surface area (minimize embodied carbon and cost of construction), maximize floor area (maximize rentable space), and maximize the roof areas (maximize solar generation potential). The outputs will include total construction cost as a function of the wall area, total solar energy potential as a function of the roof area, total embodied carbon as function wall area, and total floor area. Other inputs will include embodied carbon per surface area for each material, cost of material per area, and solar energy per area.
  • Design Variables: Building heights, Radius of top circle for each of the buildings, and Radius of bottom circle for the both of the buildings
  • Constants: Embodied carbon per surface area for each material, cost per area, Building storey heights, and solar energy per area.
  • Evaluators: Total construction material cost, Total solar energy value, Total embodied carbon, and Total floor area.
  • Interpretation: Shown in the next step

Step 3 - Generative Design Study Results

  • The screenshot of the Scatterplot of the chosen tradeoff.
  • The tradeoff shown is between the total building material cost and the solar value potentials. The objective of the study is to maximize the solar value while minimizing the building matterial cost. Looking at the scatterplot, we see that the building options with higher solar values also have higher material costs (and higher embodied carbon content as well. This graph does have some sort of a frontier which is good. Knowing this, I would I can already eliminate some design options that have really high costs and still have low solar values (the two last points on this graph for example). It would help in deciding what constraints to put for the dimensions in order to avoid these outcomes.
  • Below is my dynamo Study Graph showing my overall model workflow.
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