Yonatan Abebe - Module 8-1

Intended users

This solution's primary users are designers and real estate developers involved in the planning and designing of apartment towers.

Need you’re trying to provide a solution or support for

This solution addresses a pressing need in the industry: the lack of a streamlined process to design apartment towers that optimally utilize available lot area and maximize profit. Currently, most developers rely on Excel files to build pro forma and manually analyze the profitability of each model. This method is not only time-consuming but also prone to errors. By automating the generation of tower designs, including the basement for parking, calculating construction costs, rental revenues, yearly profit, and Net Present Value (NPV), and optimizing to get a design that maximizes NPV, the number of apartment units and parking stalls, we will reduce the time spent on manual calculations and iterations, and enhancing efficiency and accuracy in the design and planning stages.

Inputs

  • Lot Area and Required Set Back
  • Number of Floors and Height of Floors
  • Apartment Floor Area
  • Rent Range
  • Useful Life
  • Discount Rate

Underlying logic of the model you’ll implement

  1. Data Collection: Gather input values from the user, including lot area, number of floors, height of floors, apartment floor area, rent range, useful life, and discount rate.
  2. Parametric Design: Use Dynamo nodes to create a parametric model of the apartment tower. This involves generating the building footprint using point-by-coordinated nodes with input for lot size and setback. Then, using surfaces and extrusion nodes, we create the basement underground. It calculated the number of parking stalls using 144 sf/stall. Use two groups of nodes to create a podium level and the tower floors. The output from the basement, podium, and tower formation is used in logic to calculate floor areas for each section, as well as cost and revenue.
  3. Cost Calculation: Calculate the total construction cost based on the provided cost per square meter and the total floor area. The cost/SF used is $350/SF for the tower, $300/SF for the podium, and $400 for the basement. This can be changed based on the local market.
  4. Revenue Calculation: A rent range is provided as input. The revenue logic uses this and the number of apartment units (Calculated by dividing floor area * 0.8 / room area). 0.2/20% of floor area is allocated for hallways, stairs, and service areas. The room area is provided as input for generative design to use with a minimum of 700 sf.
  5. Financial Analysis: Compute the yearly profit, considering rental revenue minus construction and operational costs. Use the provided discount rate and useful life to calculate the investment's Net Present Value (NPV).
  6. Visualization and Output: Visualize the parametric model within Dynamo and Revit Case Study. Provide detailed reports on construction costs, rental revenues, yearly profits, and NPV via exported Excel document or scatter plots produced by Revit Generative Design Case Study.

Outputs

Number of parking stalls

Number of apartment units

Initial Cost

Yearly Revenue

Yearly Profit

Net Present Value of costs and benefits