In this homework, we are creating two custom nodes to evaluate the alternatives based on a custom criteria. In the homework prompt, three aspects are suggested: Building Geometry; Building Performance; Economics. Although all three factors are crucial, but considering them individually seems a little bit unrealistic. Therefore, the first custom node I designed is to consider both construction cost AND performance. We know that Dubai is a place full of rich people and companies, and a kind of luxury is to sit at the top of the world and looking down. Therefore, I like to propose that the top 30% of the floors can be sold to those rich people. And the taller they are, the more they are sold for. This would somewhat counteract the increasing cost of the construction. Also, we consider the bottom 70% to be a fixed rate of $700 for sale.
Below shows the node algorithm. On one hand, to calculate the construction cost by $500 /sqft to $1000 /sqft depending on the elevation. It also calculate the revenue on the other, by the rules mentioned above. Moreover, I need to borrow some algorithms from Module 5 to calculate the floor areas as preliminary calculations.
See below for the main page:
After successfully running the program and out put the values, let’s see what happen to the profit:
The result is both surprising and expected. We can see two trend: 1. the higher we build, the more profit is made. ( though the down payment would be larger) However, we can see an obvious diminishing effect of this increase. The marginal profit decreases as we go higher.
For the second node, we would like to throw our hat as businessperson and delve into our role as stewards of the environment.to look at the environmental impact of building this skyscraper has. According to the The Portland Cement Association, each cubic foot of concrete is responsible for roughly 16.2 pounds (or about 0.073 tons) of CO2 emissions. Also according to Akbari H. (2002), each tree can reduce carbon emissions by about 10-11 kilograms annually on average. This is equivalent to reducing approximately 40 kilograms of carbon dioxide per tree per year (10-11 kg x 3.67).
Let’s imagine the rich Dubai developers feel guilty enough to donate 30% of their to plant trees, to counteract the carbon emission due to construction. Let’s see how much carbon emission is resulted at the end.
Carbon emission is calculated by assuming 4 inch thick of concrete for each sqft, for slabs and column. For columns, we assume 400sqft throughout the building height.
See below for the dynamo screenshot and the results
Surprisingly, we see a balance point at around 450-500ft of building height. After building higher than 500ft, the increase in profit, which resulted to the increase in trees, would counteract the CO2 emissions.
In conclusion, building at the city’s limit, which is 750ft, seems to be an optimal choice in terms of profit and controlling the environmental impact.
Disclaimer: the constant used in both custom nodes are mostly approximate values. Thus this is not an accurate calculation, and further studies should be done Other metrics would be useful to compute to help understand and make the case for which alternatives are truly better than others, for example, the energy efficiency of the building throughout its life cycle would provide a more comprehensive analysis.