Generative Facades
Every panel optimized for its exact position. 38-45% less cooling load in our simulation scenarios.
In our cumulative Radiance runs, a west-facing glass facade on our Istanbul scenario massing collects about 1,420 kilowatt-hours per square meter a year. That's enough energy to cook an office.
Traditional solutions make you choose. Fixed louvers block sun but kill the view. Tinted glass reduces glare but darkens the interior. You can have comfort or daylight, not both.
The idea we test here is older than the tools. In 1981 Mike Davies sketched the polyvalent wall: a facade that filters heat, light, air, and view independently. Frei Otto found structural forms by letting physics vote. What has changed is that an evolutionary solver can now run that vote thousands of times per facade. So we asked: what if every panel was optimized for its exact position? South-facing panels deep, north-facing panels shallow, west-facing panels aggressive, east-facing panels gentle.
Method, in one line: Radiance maps a year of sun onto the massing; six parameters span 2.3 million possible panel configurations; Wallacei's evolutionary solver breeds 50 generations of 100 candidates against two objectives, cooling load and daylight; the Pareto front is where the trade-off lives; clustering compresses 3,472 winning panels into 14 buildable families.
The result, in our full-year simulations: 38-45% reduction in cooling load while keeping daylight above 50%. That's a combination fixed uniform shading cannot achieve. The numbers on this page come from those simulation runs; none of these facades has been built.
Position-Specific: Each panel responds to its unique solar exposure. The facade is a map of the sun's path.
Theoretical Framework
Solar Performance
38-45% heat gain reduction compared to clear glazing in the model. Each panel does its exact job.
Daylight Balance
Maintaining 50%+ daylight availability even with aggressive shading. Comfort and light coexist.
Panel Rationalization
3,472 unique panels clustered into 14 fabrication families. Custom performance, manageable production.
Fabrication Logic
Clustering cuts estimated CNC toolpath time by roughly 60% versus the unclustered approach. Fabrication itself is the untested step.
Research Process
Map Solar Exposure
8,760-hour simulation in Radiance, cumulative kWh/m² per zone
Define Parameters
6 variables, 2.3M configurations in the design space
Evolve Solutions
50 generations in Wallacei, Pareto front yields 15-20 optimal options
Rationalize
Cluster 3,472 panels into 14 families for efficient CNC fabrication
Research Phases
Environmental Mapping
8,760 hours of solar simulation using Radiance. Cumulative radiation mapped per facade zone.
Design Space
6 parametric variables generating 2.3 million valid panel configurations. The space is vast.
Evolution
50 generations, 100 panels per generation. Wallacei breeds toward Pareto-optimal solutions.
Fabrication
Clustering algorithm groups similar panels. CNC toolpath generation for robotic fabrication.
The Loop: One facade generation cycle: map a year of sun, span the design space, breed against two objectives, keep the Pareto front, cluster for fabrication. Numbers from our Ankara scenario run.
Key Metrics
Key Thinkers
Mike Davies
In 1981, Davies imagined a wall that could filter heat, light, air, and view independently. Per-panel optimization is a fixed-geometry step toward it, forty years later.
Klaus Daniels
Daniels wrote the book on climate-responsive building technology. Our simulation methods extend his performance modeling.
Frei Otto
Otto minimized material through form, letting physics vote on shape. We minimize energy through geometry. Same philosophy, different medium.
Jan Knippers
Knippers leads biomimetic facade research. Our panel articulation draws from his work on adaptive structures.
Case Studies
Scenario: Office Tower, Ankara
Design scenario, not builtWest-facing curtain wall with optimized aluminum louvers. Our largest simulation scenario, run on the same massing as our Data-Driven Tower concept study. Modeled cooling reduction: 38%.
Scenario: Mediterranean Pavilion, Izmir
Design scenario, not builtETFE cushion concept with variable pneumatic fill. A testbed scenario for lightweight materials. Modeled heat reduction: 42%.
Scenario: Heritage Retrofit, Athens
Design scenario, not builtHeritage-sensitive secondary skin over an existing stone facade. The hardest constraint set we've modeled: performance without touching the historic exterior. Modeled cooling reduction: 45%.
Comparative Analysis
Fixed Louvers
One Angle Fits AllStatic aluminum blades at fixed angle. Works on one orientation, fails on others.
Kinetic Facades
Moving PartsPanels that track the sun. The Al Bahr Towers report roughly 50 percent solar gain reduction from their kinetic screen: high performance, real maintenance cost.
Parametric Panels
Smooth VariationGradual geometric change across the surface. Visually striking, not necessarily optimized.
Our Approach
Per-Panel OptimizationEach panel evolved for its specific conditions, no moving parts. Best performance-to-cost ratio in our simulation runs.
Optimization Results
Percentage reduction compared to clear glazing
Scenario model: values from our own simulation runs
Key Findings
Self-shading cuts cooling 38-45% in Mediterranean climates. All three of our simulation scenarios (Ankara, Izmir, Athens) agree.
38-45% in the modelOptimal panel depth varies from 120mm (north) to 480mm (west) on a single building. Uniform shading wastes material.
4× depth variationVoronoi perforation achieves 23% higher daylight uniformity than regular grids at the same openness ratio, in our comparison runs.
+23% uniformityTopology optimization of panel geometry reduces aluminum usage by 23% in the model without compromising computed strength.
23% material savedHonest Limitations
Variable angles collect dust unevenly. Maintenance is harder than uniform systems.
Glare risk. Some configurations redirect light into eyes rather than blocking it.
Cost premium. 12-18% higher fabrication cost versus standard curtain wall, by our estimate.
Winter penalty. Aggressive shading reduces beneficial solar gain in cold climates.
Everything here is simulation. No facade from this study has been fabricated at full scale, and simulated performance always loses something on site.
References & Data Sources
Literature
Mike Davies, A Wall for All Seasons (1981)
RIBA Journal 88(2). The polyvalent wall: a facade filtering heat, light, air, and view independently.
Roudsari and Pak, Ladybug: A Parametric Environmental Plugin (2013)
IBPSA Building Simulation. The toolchain connecting climate data to parametric models.
↗David Rutten, Galapagos: On the Logic and Limitations of Generic Solvers (2013)
Architectural Design 83(2). What evolutionary solvers can and cannot promise a designer.
↗Luisa Caldas, GENE_ARCH (2008)
Advanced Engineering Informatics 22(1). Early proof that evolutionary search finds energy-efficient architecture.
↗Karanouh and Kerber, Innovations in Dynamic Architecture (2015)
Journal of Facade Design and Engineering 3. The Al Bahr Towers kinetic screen, documented by its designers.
Greg Ward, The RADIANCE Lighting Simulation and Rendering System (1994)
SIGGRAPH. The validated ray-tracer behind our 8,760-hour solar maps.
↗Conclusion
Every panel can be different and still be rationalized for fabrication. With per-position optimization, our simulations show 38-45% cooling reduction while maintaining daylight above 50%; a performance level fixed uniform shading cannot reach. The method works in the model. Building a bay of it is the honest next test.
Limitations
- Maintenance complexity
- 12-18% cost premium
Future Directions
- Fabricate and instrument a full-scale bay
- Glare analysis per configuration
- Winter-balance objectives for cold climates