Stage 1:
Screenshots:
Net Development Value Custom Node Logic:
Burj Khalifa View Score Custom Node Logic:
Revit Conceptual Mass Forms for my building and the Burj Khalifa stand-in model:
Exported Excel Data:
Modeling Process:
For Stage 1, I decided to change some of my Dynamo graph from Module 5 to make it work better and also to be more organized. I decided that my two varying inputs would be building height and a taper ratio of the building radii going up the building. So, once I had the initial process set up, it was time to decide what I wanted to evaluate.
First, I decided to evaluate the Estimated Construction Cost and the Net Development Value of the building. This custom node computes a floor-by-floor construction cost using the linear formula outlined in the project brief: $500/SF at 0ft and $1,000/SF at 750ft. To do this, I created mass floor elements that were filtered using Element ID and then matched to their proper level elevation. Then I computed the construction cost for each floor and summed the values to get a total construction cost. To calculate the Total Revenue per floor, I also assumed that the rent increased as you go up the building due to more desirable views. So, I assumed $80/SF at 0ft and $160/SF at 750ft. I then calculated the total revenue over a given time period that was controlled with a slider. Finally, I computed the Net Development Value over that time period.
Second, I wanted to evaluate a Burj Khalifa View Score the provides a value 0-1 measuring the direct sight from each panel of the building to the Burj Khalifa. To do this, I first needed to make a new conceptual mass to represent the Burj Khalifa because I couldn’t find a way to use the masses in the linked model for the view score. Once I had the mass, I panelized my building and drew sight lines that were starting at the center of each panel and were normal to the panel face. I then corrected the sight lines to all face outwards. At this point, I ran into some troubles because my sight lines were still pointing in mis-matched direction. So, I manually went in and found which faces were not working correctly and fixed them. I believe this problem had to do with the curved nature of my conceptual mass. Once I had my sight lines, I tested to see where they intersected with my Burj Khalifa conceptual mass and then computed a final score that was a ratio of the panels that had a direct line of site to the total number of panels.
Now that I had both evaluator logics, I turned each into a custom node and then integrated those custom nodes into my big custom node and then exported my results to Excel.
Points to Ponder:
I would say that each evaluator responds well to changing inputs. Additionally, each evaluator helps to provide much more valuable information than just the Gross Floor Area, Gross Surface Area, and Gross Volumes alone. First, the Net Development Value gives valuable information to the owner that would allow them to find the break-even point for each scenario. This metric responded very well to the varying inputs. The Burj Khalifa View Score Node helps to determine which building orientation will provide the best value for the building which could also help the owner make the most profit because you can charge more for a unit with a direct view. This metric did not respond super well to my varying inputs because I did not vary the rotation. Therefore, I would change that in a further iteration.
Other metrics that could be useful are solar insulation potential on the envelope or floor plate usability to help measure floor efficiency for office or apartment planning.
Stage 2:
Screenshots:
Modeling Process:
Stage 2 was completed in Excel using the data from Stage 1. I chose to evaluate 4 metrics: Gross Floor Area, Envelope Efficiency, Net Development Value and Burj Khalifa View Score. These had weights of 30%, 10%, 40%, and 20% respectively and the rationale for that will be explained in the Points to Ponder section. First, I computed the Envelope Efficiency by dividing Gross Floor Area by Gross Surface Area to measure how space efficient the building is. Then I found the minimum and maximum for each metric and then normalized the values. Finally, I applied their weights and found my total value. Then, I applied conditional formatting, and my top three options were as follows:
- Height = 680ft, Taper Ratio = 0.65
- Height = 680ft, Taper Ratio = 0.625
- Height = 600ft, Taper Ratio = 0.60
Points to Ponder:
The following outlines the logic used to determine which weights I wanted to use. I chose to weigh the Net Development Value as the largest at 40% because it directly reflects the owner’s ultimate goal of profitability. Then, I weighed the Gross Floor Area as 30% because we not only need to meet the program requirement but also need to maximize the floor area to maximize leasable space which is also important to the owner. I weighed the view score as 20% because the views are a very important aspect of the property value but some of this was already captured in the Net Development Value. Lastly, the Envelope Efficiency got a weight of 10% because it is a secondary performance signal. Ultimately, this decision came down to the tradeoff between height and taper and this way of weighing the metrics give us the most real-world scenario.
The recommended design alternative was based solely on the final weighted score that was based on the logic above. At the taller height, the construction costs are a little higher but remain manageable while the total revenue also increases. This was the most influential and also had to do with the higher taper ratio. With this weighing scheme, I think that the Burj Khalifa View Score got a little lost, but this was also not a great metric given the effectiveness of this node.
Stage 3:
Screenshots:
Modeling Process:
For Stage 3, I used the selected design alternative and made a code block with its input values. Then I panelized the wall surfaces of my conceptual mass and applied the rectangular panel with opening adaptive panel. I had trouble getting the adaptive elements to show up on 3 of the faces but I think that might have to do with the geometry of my conceptual mass. Then I computed solar directness values for each panel and remapped the ranges to scale the panel openings. I also applied logic to change the color of the panels as well as the panel opening width.
Points to Ponder:
This is the best alternative because it scored the highest in our Stage 2 evaluation. Visualizing this panelization helped to see why this was the best alternative. The main limitation to this Stage was that I evaluated the solar directness rather than the Burj Khalifa View Score. If I were to do this again, I would used that metric instead so I could better visualize the design alternative.