Bring reuse to the people: an intuitive digital building inventory tool

AI Quick Summary

We propose to develop an open-source smartphone app to simplify the process of documenting building components for reuse. Users take pictures to capture type, material, and dimensions with the help of a computer vision model, and an experience database assigns each component a color-coded reuse potential. This tool will accelerate assessments, make reuse more accessible, and empower both non-experts and professionals in the circular built environment. What challenge in the circular building and construction industry does your idea address?Growing the circularity industry requires planning certainty, but a lack of reuse data on the existing building stock hinders the ability to inventory at scale. Moreover, the current practice of employing circularity auditors to evaluate reusable elements on site is time intensive and costly. What is your vision for solving this challenge, and why is your approach innovative? Who will benefit from a solution to this problem?Circularity experts excel at determining what can be reused, yet much of their time is spent on manual documentation. What if reuse were accessible to everyone, allowing experts to focus on what truly matters? We envision a simple, open-source, smartphone-based inventory tool that empowers non-experts to document and assess building elements for reusability.This approach transforms the assessment process by separating data collection from expert analysis. With its open-source framework, the tool paves the way for a unified, standardized collection process, driving a systemic shift in the Swiss circularity ecosystem. Our solution benefits multiple stakeholders: building owners receive faster, more affordable assessments of reusable elements, circularity auditors increase efficiency, and the reuse market gains resource visibility among non-expert audiences. The app’s ability to provide near-instantaneous, automated pre-selection of reusable elements will free experts from the responsibility of basic documentation and, in turn, improve and popularize existing reuse workflows.Instead of multiple proprietary tools, experts can also co-develop a standardized open-source solution, focusing on specialized services rather than redundant data collection. The existing reused material markets and experts from various fields can contribute their knowledge and services, whether in reuse assessment, matchmaking, or certification. How could your idea positively impact the planet, people, or economy in the future? (e.g., circularity, reducing waste, improving health, creating opportunities)Transitioning to a circular economy is essential, but its success depends on human engagement and economic potential. The smartphone app that we wish to develop will directly engage people and create new economic opportunities for construction stakeholders and services. It will also raise awareness of circularity by making the value of existing structures more visible. Moving away from isolated efforts to a connected network can trigger a butterfly effect, where localized actions drive systemic change, amplifying our impact on waste reduction, resource conservation, and economic resilience. The open-source nature of the application makes this movement accessible to everyone.What assumptions or ideas do you want to test? What do you plan to work on during the booster program, and what is your goal to deliver at the end? (e.g., feasibility testing, prototype development, testing desirability)Our project focuses on developing a prototype smartphone application to test the hypothesis that accessible, non-technical inventory tools can improve the documentation of reusable building components and ultimately promote reuse in previously “non-circular” construction projects. The prototype will integrate smartphone camera functionality for seamless on-site documentation. Users will take photos within the app, where AI-powered recognition will automatically identify building components and suggest attributes such as type, material, color, and dimensions. An easy-to-use interface will enable users to review and correct the identified properties, ensuring accuracy. A preliminary reuse assessment using a color-coded system (green, orange, red) will help determine the reuse potential from both a carbon and financial perspective.During CBI Booster, we will develop the prototype. We aim to collaborate closely with industry partners and integrate stakeholder feedback from within the CBI Booster network and the circularity domain. The prototype's usability will be tested throughout the program to ensure its usefulness for and integration into established workflows.By the end of CBI Booster, we aim to deliver a working prototype demonstrating technical feasibility. Furthermore, we will provide a detailed action plan outlining technical refinements, data management strategies, integration with reuse marketplaces, and socio-technical considerations for broader adoption.Has your idea been tested before? If yes, what were the results, and what remains to be tested? Existing inventory tools are proprietary, auditor-focused, and lack broad compatibility. Existing component detection often uses photogrammetry, 3D laser scanning, and AI to produce accurate but costly, computationally intensive, and hence impractical solutions for on-site workflows. In 2024, we began research on deep learning computer vision (CV) to recognize materials and segment components, and extract key data. We have already developed a reusability experience database that will act as information support to automate information retrieval and predict reusability in the prototype. An open, smartphone-compatible CV approach using standard cameras and the integration of the recommender system is yet to be developed.Who is in your team, and what expertise or roles do they bring?Ana Bendiek Laranjo (PhD candidate, Urban Energy Systems, Empa (UES); affiliated with Circular Engineering for Architecture, ETH Zurich) has industrial experience in site management and research expertise in digitizing inventory processes using deep learning CV. Dr. Jens Hunhevicz (Postdoc, UES) researches technology-enabled governance. He has experience in construction execution and planning, supply chain management, and coordinating research projects. Benoît Seraphin (architect, Oïkos; researcher, HEPIA Genève) specializes in design, circular construction, and material reuse strategies. Almir Delfieu (architect and civil engineering student, HEPIA Gèneve) has collaborated with Benoit over three years to develop a reuse evaluation matrix for commonly used materials.The strength of our team lies in our diverse backgrounds. We bridge civil engineering and architecture, industry and research, and the different linguistic and cultural regions of Switzerland. Our multidisciplinary expertise combines the technical knowledge, practical experience, and insight into building reuse strategies necessary to execute the project scope successfully.How do you plan to secure the 10% third-party funding required?The fragmentation and complexity of the construction industry pose significant challenges to implementing circular strategies. Stakeholders have different perspectives on integrating digital tools. When selecting third-party funding partners, we look for industry stakeholders with diverse foci within construction and strong interest in circular business models. Ideally, they have expertise in deconstruction, pre-demolition audits, reusability assessments, and a profound understanding of the construction value chain. We have strong connections in Switzerland and internationally through our work in circular construction and have already started discussions with Implenia AG as a potential partner and have agreed to involve them in the next steps.

Project Idea Metadata

Project Idea Name: Bring reuse to the people: an intuitive digital building inventory tool
Date: 4/9/2025 4:31:37 PM
Administrators:
- Ana Bendiek Laranjo

Project Idea Description

What challenge in the circular building and construction industry does your idea address?

Growing the circularity industry requires planning certainty, but a lack of reuse data on the existing building stock hinders the ability to inventory at scale. Moreover, the current practice of employing circularity auditors to evaluate reusable elements on site is time intensive and costly.

What is your vision for solving this challenge, and why is your approach innovative? Who will benefit from a solution to this problem?

Circularity experts excel at determining what can be reused, yet much of their time is spent on manual documentation. What if reuse were accessible to everyone, allowing experts to focus on what truly matters? We envision a simple, open-source, smartphone-based inventory tool that empowers non-experts to document and assess building elements for reusability.

This approach transforms the assessment process by separating data collection from expert analysis. With its open-source framework, the tool paves the way for a unified, standardized collection process, driving a systemic shift in the Swiss circularity ecosystem.

Our solution benefits multiple stakeholders: building owners receive faster, more affordable assessments of reusable elements, circularity auditors increase efficiency, and the reuse market gains resource visibility among non-expert audiences. The app’s ability to provide near-instantaneous, automated pre-selection of reusable elements will free experts from the responsibility of basic documentation and, in turn, improve and popularize existing reuse workflows.

Instead of multiple proprietary tools, experts can also co-develop a standardized open-source solution, focusing on specialized services rather than redundant data collection. The existing reused material markets and experts from various fields can contribute their knowledge and services, whether in reuse assessment, matchmaking, or certification.

How could your idea positively impact the planet, people, or economy in the future? (e.g., circularity, reducing waste, improving health, creating opportunities)

Transitioning to a circular economy is essential, but its success depends on human engagement and economic potential. The smartphone app that we wish to develop will directly engage people and create new economic opportunities for construction stakeholders and services. It will also raise awareness of circularity by making the value of existing structures more visible. Moving away from isolated efforts to a connected network can trigger a butterfly effect, where localized actions drive systemic change, amplifying our impact on waste reduction, resource conservation, and economic resilience. The open-source nature of the application makes this movement accessible to everyone.

What assumptions or ideas do you want to test? What do you plan to work on during the booster program, and what is your goal to deliver at the end? (e.g., feasibility testing, prototype development, testing desirability)

Our project focuses on developing a prototype smartphone application to test the hypothesis that accessible, non-technical inventory tools can improve the documentation of reusable building components and ultimately promote reuse in previously “non-circular” construction projects.

The prototype will integrate smartphone camera functionality for seamless on-site documentation. Users will take photos within the app, where AI-powered recognition will automatically identify building components and suggest attributes such as type, material, color, and dimensions. An easy-to-use interface will enable users to review and correct the identified properties, ensuring accuracy. A preliminary reuse assessment using a color-coded system (green, orange, red) will help determine the reuse potential from both a carbon and financial perspective.

During CBI Booster, we will develop the prototype. We aim to collaborate closely with industry partners and integrate stakeholder feedback from within the CBI Booster network and the circularity domain. The prototype's usability will be tested throughout the program to ensure its usefulness for and integration into established workflows.

By the end of CBI Booster, we aim to deliver a working prototype demonstrating technical feasibility. Furthermore, we will provide a detailed action plan outlining technical refinements, data management strategies, integration with reuse marketplaces, and socio-technical considerations for broader adoption.

Has your idea been tested before? If yes, what were the results, and what remains to be tested?

Existing inventory tools are proprietary, auditor-focused, and lack broad compatibility. Existing component detection often uses photogrammetry, 3D laser scanning, and AI to produce accurate but costly, computationally intensive, and hence impractical solutions for on-site workflows.

In 2024, we began research on deep learning computer vision (CV) to recognize materials and segment components, and extract key data. We have already developed a reusability experience database that will act as information support to automate information retrieval and predict reusability in the prototype. An open, smartphone-compatible CV approach using standard cameras and the integration of the recommender system is yet to be developed.

Who is in your team, and what expertise or roles do they bring?

Ana Bendiek Laranjo (PhD candidate, Urban Energy Systems, Empa (UES); affiliated with Circular Engineering for Architecture, ETH Zurich) has industrial experience in site management and research expertise in digitizing inventory processes using deep learning CV. Dr. Jens Hunhevicz (Postdoc, UES) researches technology-enabled governance. He has experience in construction execution and planning, supply chain management, and coordinating research projects. Benoît Seraphin (architect, Oïkos; researcher, HEPIA Genève) specializes in design, circular construction, and material reuse strategies. Almir Delfieu (architect and civil engineering student, HEPIA Gèneve) has collaborated with Benoit over three years to develop a reuse evaluation matrix for commonly used materials.

The strength of our team lies in our diverse backgrounds. We bridge civil engineering and architecture, industry and research, and the different linguistic and cultural regions of Switzerland. Our multidisciplinary expertise combines the technical knowledge, practical experience, and insight into building reuse strategies necessary to execute the project scope successfully.

How do you plan to secure the 10% third-party funding required?

The fragmentation and complexity of the construction industry pose significant challenges to implementing circular strategies. Stakeholders have different perspectives on integrating digital tools. When selecting third-party funding partners, we look for industry stakeholders with diverse foci within construction and strong interest in circular business models. Ideally, they have expertise in deconstruction, pre-demolition audits, reusability assessments, and a profound understanding of the construction value chain. We have strong connections in Switzerland and internationally through our work in circular construction and have already started discussions with Implenia AG as a potential partner and have agreed to involve them in the next steps.