Hey, my name is Silas. Welcome to my website!
I studied civil engineering at Stuttgart University of Applied Sciences, Universidad de Jaén (Spain), and the University of Stuttgart. From March to June 2025, I joined Lawrence Berkeley National Laboratory in California as a visiting researcher, working on reinforcement learning for building energy systems.
Currently, I am a research and teaching assistant at the Institute for Lightweight Structures and Conceptual Design (ILEK) at the University of Stuttgart, where I am completing my doctoral dissertation under Prof. Dr.-Ing. M.Arch. Lucio Blandini.
My research focuses on reinforcement learning for the control of adaptive facade systems, specifically switchable glazing. The goal is to optimize both energy efficiency and occupant comfort (thermal and visual) through intelligent, data-driven control strategies.
Beyond my core research, I am passionate about sustainable architecture, digital manufacturing, and innovative technologies that support a climate-friendly built environment.
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2026-10-07 — Publication: Systematic Reward Shaping for Deep Reinforcement Learning Control of Adaptive Facades
Silas Kalmbach, Christoph Gehbauer, Lucio Blandini, José Baptista
2026 International Conference on Smart Energy Systems and Technologies (SEST), Ciudad Real, Spain, pp. 1–6
doi.org/10.1109/SEST67798.2026.11712368
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2026-09-03 — Talk: Systematic Reward Shaping for Deep Reinforcement Learning Control of Adaptive Facades
Silas Kalmbach, Christoph Gehbauer, Lucio Blandini, José Baptista
SEST26 — 8th International Conference on Smart Energy Systems and Technologies, Ciudad Real, Spain
Presenting “Systematic Reward Shaping for Deep Reinforcement Learning Control of Adaptive Facades” at SEST26, the 8th International Conference on Smart Energy Systems and Technologies in Ciudad Real, Spain. The talk showed that observation normalization is the decisive factor for training DRL agents on buildings: without it, the agents never learn. With it in place, an agent trained purely on visual comfort cut glare violations sevenfold against static clear glazing — while using less primary energy than a rule-based controller, without ever optimizing energy directly. The underlying paper appears in the SEST26 conference proceedings.
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2026-07 — Outreach: 2nd KI-Stammtisch, AKBW
Second KI-Stammtisch at the AKBW Architektenkammer Baden-Württemberg (July 2026): Experts and practitioners joined on-site and online to discuss the practical use of AI agents in architectural offices. I contributed to the panel discussion representing ILEK, University of Stuttgart.
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2026-06 — Outreach: KI-Kodex Workshop II, Architektenkammer Berlin
Second KI-Kodex workshop at the Architektenkammer Berlin (June 2026): Concretizing principles and shaping responsibility — refining and prioritizing the regulatory proposals from the first workshop into a clear, practice-oriented compass for the planning profession.
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2026-05 — Outreach: KI-Kodex Workshop I, Architektenkammer Berlin
Contributing to the KI-Kodex for the planning professions: At the first workshop hosted by the Architektenkammer Berlin (May 2026), experts from across Germany started developing practical professional guidelines for the responsible use of AI in architecture and planning — covering sustainability, fairness, data protection, copyright, and accountability.
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2026-03-03 — Talk: FRADS-GYM: A Reinforcement Learning Framework for Holistic Building Automation with Energy and Daylight Simulation
Silas Kalmbach
deRSE26 — 6th Conference for Research Software Engineering in Germany, Stuttgart
doi.org/10.5281/zenodo.18854194
Presenting FRADS-GYM at the deRSE26 conference: A novel reinforcement learning framework that bridges the gap in building control by bringing daylight simulation into the loop. By seamlessly coupling EnergyPlus and Radiance, it empowers researchers to train intelligent agents for adaptive facade control. Optimizing both energy efficiency and visual comfort. A huge step towards reproducible, config-driven research for sustainable architecture.
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2026-02-18 — Publication: Thermal behaviour of switchable liquid crystal glazing under real environmental conditions
Silas Kalmbach, Walter Haase, Jens Osterodt, Lucio Blandini
Glass Structures & Engineering 11 (1), Art. 4
doi.org/10.1007/s40940-025-00313-3
On the cover of Glass Structures & Engineering, Volume 11, Issue 1 (2026): an inside-out view through the switchable liquid crystal glazing of ILEK's Facade Test Building, the triple glazing units held in different switching states — a figure from our study in that issue. Over three years (2022–2024) we measured how the panes heat up under real weather conditions: temperatures ranged from −9.9 °C to 79.9 °C, and the difference between pane centre and clamped edge reached 47.9 °C, above the 40 °C limit DIN EN 572-1 sets for float glass. Still no pane fractured, which suggests the LC units tolerate more thermal stress than expected. The monitoring campaign is laid out to run for up to ten years.
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2026-02-06 — Software: frads-gym v0.1.1 — Initial Release
Silas Kalmbach
Research software, archived on Zenodo
doi.org/10.5281/zenodo.18504305
FRADS-GYM is the open-source backbone of my research: a Gymnasium environment that couples EnergyPlus and Radiance, so reinforcement learning agents for adaptive facades can be trained on energy and daylight at once. Released under an open licence, installable with a single pip install and archived on Zenodo for citable, reproducible experiments.
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2025-12-04 — Interview: Adaptive Fassaden: minimaler ökologischer Fußabdruck und maximale klimatische Anpassungsfähigkeit
Building Technologies · Messe Frankfurt
Smart Building Façades for Sustainable Performance: Adaptive systems for energy efficiency and comfort. Exploring how intelligent control strategies can optimize facade behavior.
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2025-11-17 — Outreach: Premiere of the KI-Stammtisch, AKBW
Premiere of the AI Roundtable on Nov 17 2025 at AKBW Architektenkammer Baden-Württemberg. Discussing the future of AI in architecture. It was a great opportunity to exchange ideas with other architectural offices and researchers on the application of AI in our field.
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2025-05-08 — Dataset: Data for: Thermal behaviour of switchable liquid crystal glazing under real environmental conditions
Silas Kalmbach, Walter Haase, Jens Osterodt, Lucio Blandini
DaRUS — Data Repository of the University of Stuttgart
doi.org/10.18419/darus-5044
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2024 — Publication: Entwicklung adaptiver Membranfassadenmodule
Walter Haase, Christina Eisenbarth, Silas Kalmbach, Jan Bolay
BBSR-Online-Publikation 83/2024
doi.org/10.58007/cktw-py23
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2022-05 — Publication: Ganzheitliche Raumregelungen mit maschinellem Lernen individuell gedacht
Silas Kalmbach, Walter Haase, Lucio Blandini
1. Fachkongress Konstruktiver Ingenieurbau, Technische Akademie Esslingen
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2020-09 — Publication: Anwendung von Methoden des maschinellen Lernens zur ganzheitlichen Raumregelung
Silas Kalmbach, Walter Haase, Werner Sobek
BauSIM 2020 — 8th Conference of IBPSA-Germany and Austria, TU Graz
ILEKlab1244 is a teaching format at the Institute for Lightweight Structures and Conceptual Design (ILEK), University of Stuttgart, that links architecture and civil engineering students directly to the research of the Collaborative Research Centre SFB 1244 on adaptive building skins and structures. Instead of a fixed brief, students develop their own question, test it with prototypes and document it in a booklet. From 2019 to 2025 I supervised the lab together with Irina Auernhammer, Katrin Chwalek and Amay Shah.
- Individualität im Modularen Bauen, SS 2023, Thesis, by Anne Steinmetz
How can modular construction, efficient and sustainable by nature, still leave room for individual ways of living and working? A set of flexible, non-load-bearing interior walls that can be repositioned within the modules: thermal storage, furniture and plug-in walls, textile and sliding walls, made of regional, recyclable materials. A catalogue of wall types and scenarios showing how adaptive floor plans can follow their users over time, across different building typologies.
- Wandelbarkeit im Modularen Bauen, SS 2023, Thesis, by Masha Holzmann
How can a building change its use several times and adapt to the life cycle of its occupants, while new construction is weighed against resource scarcity and lack of space? An extendable, adaptive building envelope that combines modularity, lightweight construction, adaptivity and sustainability; prefabricated façade modules can be added, swapped and reused. A façade system whose second, adaptive layer changes the building volume and harvests solar energy, extending the building's service life through easy replacement of parts.
- connect@façade, WS 2022/23, Seminar, by Johanna Büttner, Magnus Huber, Markus Pfaff
The pandemic made loneliness visible as never before. How can the built environment bring people physically back together after times of isolation? A guidance system that uses building façades, a large and mostly unused surface, as its medium: large-scale augmented reality combined with selective physical façade panels, so everyone has easy access. A hybrid wayfinding concept for the city, with a guidance network, app screens and physical panel prototypes.
- eᶠ: Energy to the Power of the Façade, WS 2022/23, Thesis, by David Bijelonjic, Pavel Walter
Can a single modular façade harvest energy from both sun and wind? A weather-adaptive, modular façade whose functions are controlled by sensors and AI. A façade concept for energy generation from solar and wind exposure, shown in façade and interior renderings and a physical prototype.
- Aqua-façade, SS 2022, Thesis, by Abdelrhman Ibrahim
How can a façade secure drinking water independently of region, water mains or local conditions? Warm, humid air condenses on cooled façade elements at the dew point. A diagonal gutter leads the condensate through a glass funnel into a four-stage filter. Façade sensors and weather forecasts feed a central system that predicts dew point, energy demand and water yield. A façade element that produces drinking water and, while running, releases heat that can be used indoors.
- Hypar Pavilion, WS 2024/25, Design studio, by Biyu Li, Junzhe Zhao, Mariia Hruntes
How can the knitted membrane panels of the "Common Thread" pavilion be reused as a covered, adaptive pavilion linking the two SFB 1244 platforms? Models from 1:100 to 1:20 tested module layouts, rope control points and stitched connections. Fiberglass rods, steel cables and guide pulleys form a kinetic cable-pull system, checked by structural analysis for cable force, snow and wind. A modular textile pavilion whose reused 3D-knit panels unfurl and contract like leaves, driven by cables and responding to weather and user activity.
- EcoMotion, SS 2024, Design studio, by Sena Yildiz, Zeynep Tuncel
How can a high-rise façade generate renewable energy and make that generation visible? Small vertical-axis wind turbines at the façade corners and piezoelectric ribbon elements in a woven aluminium skin convert wind into electricity, tested in hairdryer experiments with LEDs and a multimeter. A double-skin façade of woven, white-coated recycled aluminium bands that lets wind and light through, shades the interior and lights LEDs as an indicator of the energy it produces.
- Reminiscence, WS 2023/24, Design studio, by Jan Krieger, Lennart Dolderer
How can a façade element reflect how people look at a place and strengthen their connection to local context? Eye-tracking data of people looking out of an opening is turned into a heatmap, which a Grasshopper script converts into the layout of hemp fibres that a six-axis robot winds into a frame. The prototype is a model with a manually plotted heatmap. A façade element that opens up where views were frequent and long and stays closed where nobody looked, so it acts as a filter that mirrors the gaze of its users.
- The Hub, WS 2023/24, Design studio, by Hümeyra Icöz, Karen Bassem Boshra Thabet
How can a façade overcome the separation between people, inside and outside, and people and nature, while giving students on campus good food and places to meet? After a campus survey with 41 students, a net spans the demonstrator tower up to the fifth floor, where fruit and vegetables are grown, harvested and tended together. Above it, vertical planting continues on both towers behind a grid shell. A planted façade that links the two towers, with a bridge widened into a loop and a net whose plants follow the movement of the sun.
- TimberFlex, SS 2024, Design studio, by Raya Allataifei, Jane Schaffhauser, Domenico Sofo
How can a secondary skin improve the thermal performance of glazed curtain walls without relying on mechanical systems? Wood veneers respond to humidity by curling. They were tested on paper and veneer models, with delignification and misting experiments, and combined into modular hexagonal panels on a 1:3 physical model. A hygroscopic double-skin façade whose wooden hexagon modules curl open when a misting system raises humidity in the cavity, opening the skin passively.
- TIMELESS, SS 2024, Design studio, by Feng Jiao, Wei Hong
How can an adaptive façade serve different needs across the day, from light and heat control to a night-time display? Square panels on a modified differential gear mechanism with servo motors rotate horizontally and vertically, tested on a 330 x 350 mm and a 520 x 630 mm façade section and a physical prototype with an Arduino-driven servo circuit. A modular, multimodal façade that shades and generates solar power by day and, at night, turns selected panels into an interactive pixel screen for information and advertising.
- Algae Flow, SS 2023, Seminar, by Masha Holzmann, Anagha Rangarajan Narasimha
How can a façade produce renewable energy directly on site in dense cities and at the same time bring nature back into them? A hexagonal tube system carries microalgae whose biomass is used for energy. Different species adapt the façade to location and season; Haematococcus pluvialis, for example, turns from green to red in summer. An adaptive second façade for new and existing buildings that generates renewable energy, reduces fossil fuel demand and adds visual value.
- Realect, SS 2023, Design studio, by Robin Paule
How can a façade counteract the loneliness caused by social media and the pandemic by bringing people into intuitive everyday interaction? A modular façade element works like a screen but is transparent when switched off: each pixel is a PDLC film on a polycarbonate plate, lit by LEDs in the frame. A camera detects people and responds to them. A prototype of 2 by 2 pixels and a program that shows how movements can be interpreted, with the aim of getting two people to play a short game together.
- Adaptive Learning Spaces, WS 2021/22, Thesis, by Mykola Tsyharin
How can a learning space adapt to the content being learnt by blending digital information with physical architecture? A projection-mapping set-up with three projectors covers two walls and the ceiling of a 5x5 m room. A Unity program turns the chapters and cross-references of a PDF book into a 3D structure and projects it onto the room's inner façade panels as colour, light and texture. A demonstrator that augments a room into a personal memory palace for learning, as a first step towards spaces that act as an interface to information.
- EnergieWände, WS 2021/22, Design studio, by Clemens Stock, Thomas Boltres
How can a façade make energy generation, storage and use visible so that people gain a new awareness of their everyday energy consumption? Adaptable interior uses such as sports equipment generate energy that pumps water into visible containers in the façade, storing it as potential energy like a pumped-storage plant. Releasing the water generates energy again and shows the energy balance inside. A façade of eleven rotatable single elements with solar elements on the outside, whose movement accompanies the energy states and which allows flexible use of one space.
- FreiRaum, WS 2021/22, Design studio, by Konrad Bornemann, Kolja Traulsen
How can buildings answer the many monofunctional spaces of today and offer room for many different uses? FreiRaum is a free, open-ended space available to everyone, applied to the whole demonstrator so that different uses can happen on different floors at the same time. An adaptive façade with adjustable opening degree dampens sound and can shield the interior from the outside. A usage-open building in which, for example, a band on one floor plays for dancers below, with concept pictograms, perspectives and a façade prototype.
- SENSORUM, WS 2021/22, Design studio, by Indiana Courarie-Delage, Felipe Zach
What influence does the environment have on people, and how can everyday university life deal actively with stress? The room plays with the senses through light, colour, sound, temperature and materials and offers four exercises: laughing, writing, sleeping and meditating. A double-layer façade protects the interior while an inner membrane filters the stimuli installed in the space between. A room that takes on the configuration and mood its visitors need, as a metaphor for human needs such as safety, joy, relaxation and reflection.
- atmosymbiosis, WS 2020/21, Design studio, by Mykola Tsyharin, Amay Shah, Lukas Maier
What could an atmosphere generated by an artificial intelligence look like, tailored to the one person who experiences it? An AI is pre-trained on the person's own photos and videos and learns how colours and sounds relate to time of day and pulse. During the interaction an ECG sensor closes the loop between person and AI, so it keeps adapting the generated colours and sounds. A demonstrator built for the project in which a continuously learning, personal atmosphere can be experienced.
- Selektive Architekturwahrnehmung, WS 2020/21, Design studio, by Christian Nopitsch, Claire Oswald, Mona Entenmann
How does selective human perception shape the way we experience architecture, and what role can artificial intelligence play as a complement to the human senses? The work starts from the thesis that perception is inherently selective and is restricted further by stimulus-intense architecture. It examines the relationship between architecture, selective perception and AI in three scenarios over time. The scenarios run from AI as a supporting tool, via a cyborg-like fusion that partly lifts the selection of perception, to humans and AI meeting on equal terms, which requires rules for AI and architecture that can handle a stimulus-rich environment.
- ToxSense, WS 2020/21, Design studio, by Maria-Catrinel Radulescu, Markus Pfaff, Timo Bilhöfer
How can people sense the toxicity of urban air, which they cannot easily recognise in everyday life? A worn headband with a camera, power source and minimal actuators sends haptic warning impulses, guiding the wearer along safer routes. A machine-learning model estimates air quality from photos of the surrounding air, and the data feeds a public real-time map. A wearable prototype with a phone app and an online map that acts as a new sense and could inform healthier urban planning.
- Colorful Workspace, WS 2023/24, Design studio, by Alica Csapo, Ellen Kern
How can an office support concentration and creativity, and make people want to come back to it? Translucent acrylic panels in yellow, red and blue are moved by stepper motors in a window frame; overlaps create orange, green and purple. An AI trained on webcam images recognises emotions such as focus or creativity and steers the panels. A working prototype that colours the sunlight in the room according to the detected mood, and a simulation of day and seasons. The authors expect good personalisation only after months of data collection.
- Re:vive – MyFacade, WS 2022/23, Seminar, by Christian Nopitsch, Nojin Haji
How can a building façade repair itself the way skin heals and scars, so that components are used to the end of their life instead of being replaced? Damaged spots are substituted with self-growing mycelium. Its growth was observed and documented for seven days under different environmental conditions, in a lab jar and in concrete and plaster moulds. A speculative future design: a drone that detects damaged spots in the city with AI and maintains the conditions mycelium needs to grow, so the building's history becomes visible through its repairs.
- Sunlight Sandbox, WS 2022/23, Design studio, by Shuang-Ying Xu, Yu-Xin Qiu, Sienna Xin Sun
How can a façade manipulate sunlight in real time and continuously, with targeted adjustment for different areas at once, while staying light, unit-based and easy to maintain? Modular double-layered inflatable units are inflated and deflated by pumps and valves, steered by an agent-based simulation and light sensors. Three preset modes (shading, moderate, transparent) respond to sun conditions and user requirements. A coloured inflatable façade that adapts shading to human activity and creates a vivid tactile atmosphere indoors, tested with a physical prototype of eight units.
- Waçade, WS 2022/23, Design studio, by Anne Steinmetz, Moritz Sailer
How can water self-sufficiency work on a small scale for a building, independent of mains and external supply? A closed-loop concept collects rain water via roof and façade, filters it through sand, particle, membrane and bio filters and disinfects it with UV elements hinged to the façade. A dry-separation toilet reduces demand, and the feasibility was calculated from rainfall and sun data. A hanging, movable façade of UV disinfection elements that is one part of a hypothetical drinking-water loop, cools in summer, warms in winter and forms an access balcony that extends living space.
- Synästhetische KI, WS 2021/22, Thesis, by Timo Bilhöfer
Can artificial intelligence support architects in the aesthetic design of space, or will it make the profession obsolete? A piece of music stands in for the whole context of a design. An AI is trained on clay-modelled and 3D-scanned forms that the designer links to music, then generates scaleless objects as proposals for spatial form, which the designer reinterprets and feeds back to the AI. An experimental, symbiotic design method between human and AI. Without curated input and carefully selected output, AI will not produce good architecture; it offers architects a creative tool and a route to a more individual aesthetic.
- Exchange, SS 2021, Design studio, by Mai Thi Nguyen, Fabio Baguhl
How can a system of decentrally acting actuators adapt itself to changing environmental conditions, here the CO2 content and thus the air quality of indoor spaces? Modelled on the slime mould Physarum polycephalum, a multi-agent simulation is translated into physical modules of 3D-printed PLA elements. CO2 sensors and Arduino-controlled servomotors fold the chains between two formations. A prototype of one active and one passive module that opens and closes as a spatial indicator of the right moment to ventilate.
- Express, SS 2021, Design studio, by Amay Shah
Can giving shape to personal trauma in clay become a medium of healing for individuals, and what effect does it have on society? Participants mould their object of trauma in clay in private spaces; the objects are recorded by photogrammetry, converted into 3D models and printed in a public viewing gallery. A private-public architecture in which the merged objects are eventually crushed, relieving people metaphorically of their trauma and giving the public an accessible way to talk about it.