High-Performance Roof Prioritization Assistant
Intended users
- Architects designing high-performance buildings
- Sustainability consultants seeking optimal roof strategies for LEED / resilience / carbon reduction based on client priorities
- Building owners and developers making investment decisions about rooftop PV, green roofs, and stormwater management
Need you’re trying to provide a solution or support for
Designers and owners face complex trade-offs when allocating roof space between solar PV, green infrastructure (green roofs / stormwater retention), and managing structural costs. Decisions typically prioritize one factor (cost or sustainability), without a holistic view of combined performance. This tool helps users make informed, balanced design choices by calculating an aggregate Sustainability / Resilience / Cost Score based on user-defined priorities — supporting transparent decision-making in early design phases.
Inputs
- User-defined priority weights (%)
- Sustainability Weight (%) → prioritizes operational emissions reductions
- Resilience Weight (%) → prioritizes stormwater retention benefits
- Cost Weight (%) → prioritizes minimizing net cost
- Design Variables
- % of roof area allocated to PV, % of roof area allocated to green roof
- Location (to determine feasible electricity generation per square foot)
- Structural system parameters (allowable load)
- Financial factors (PV costs, green roof costs, utility rates, incentive rates)
Underlying logic of the model
- Each dimension (sustainability, resilience, and cost) is scored on a 1-10 scale based on performance
- Sustainability: tCO₂e emissions avoided (via PV + battery) → mapped to category 1-10
- Resilience: % stormwater retained → mapped to category 1-10
- Cost: Net cost = (PV cost + green roof structural cost) - avoided utility costs → mapped to category 1-10 (lower net cost = higher score)
- User-input weights are applied to each score
- Overall score = (Sustainability Weight × Sustainability Score) + (Resilience Weight × Resilience Score) + (Cost Weight × Cost Score)
- The tool automatically evaluates various combinations of roof allocation (PV vs green roof) to identify options that best align with user-defined priorities.
Outputs
- Overall Sustainability / Resilience / Cost Score for each evaluated design option
- Visualization: Parallel coordinates and scatter plot of design options, highlighting where overall scores are the highest
- Breakdown of:
- tCO₂e saved annually
- Volume of stormwater retained
- Net system cost and payback period
- Structural costs from the green roof