Understanding the Deduction Rate in ArkDesign.AI
The deduction rate is a key calculation parameter in ArkDesign.AI that defines the difference between a building’s gross area and its net leasable or sellable area. Because it directly shapes revenue projections, unit yield, and feasibility outcomes, the deduction rate is one of the most influential factors in development economics.
Where to Find the Deduction Rate Setting
Within ArkDesign.AI, the deduction rate is located in the Settings menu of the Schematic Section screen.
To access it, click the gear icon in the top-left corner. From there, users can input the percentage of the gross floor area allocated to non-leasable components such as:
- Circulation spaces
- Mechanical rooms
- Service areas
- Other building support spaces
Typical Deduction Rate Ranges
Deduction rates commonly range from 15% to 25%, though they may vary depending on:
- Building type
- Core and circulation efficiency
- Market expectations
- Project complexity
Highly efficient buildings—with optimized cores and minimal horizontal circulation—may achieve deduction rates as low as 12%.
Conversely, buildings with irregular geometries, large amenity programs, or extensive service areas may exceed 25%.
Why the Deduction Rate Matters
The deduction rate directly affects multiple critical project metrics:
1. Net Rentable/Sellable Area
This is the area that generates revenue. A higher deduction rate reduces the net usable area and impacts overall financial performance.
2. Unit Count
More deductions mean less space available for residential or commercial units, influencing density and layout options.
3. Cost Efficiency
Construction cost per rentable square foot increases when the deduction rate is higher, affecting feasibility margins.
How ArkDesign.AI Uses the Deduction Rate
ArkDesign.AI integrates the deduction rate into all automated area and efficiency calculations. As users explore massing options, unit layouts, or core placements, the platform provides real-time feedback on how design decisions impact the net area and overall building efficiency.
Experimenting with deduction rate assumptions also allows teams to run sensitivity analyses, helping developers and architects understand the financial implications of different design strategies.
Professional Recommendation
When establishing deduction rate assumptions, teams should research local market benchmarks and collaborate with experienced developers or brokers familiar with the target building type. Aligning model inputs with regional norms ensures more accurate feasibility studies and realistic project outcomes.
