ConQuote Connect: A Unified Construction Platform Integrating BIM, and Blockchain Escrow

Abstract

ConQuote Connect is a smart digital platform designed to solve common problems in the construction industry, such as unclear project details, payment delays, miscommunication and the difficulty of finding trustworthy contractors. It creates a single, streamlined space where builders can post their construction projects and contractors can submit structured and easy to compare quotations. A key part of the system is the use of Building Information Modeling (BIM), which allows builders to upload 3D models of their projects. These models help both parties clearly understand the scope of work and visually track progress through milestones, such as marking when the foundation, floors, or roofing are completed. To make payments more secure, transparent, and fair, ConQuote Connect uses blockchain-powered smart contracts. These contracts safely hold project funds and only release payments when a builder confirms that a milestone has been completed through the BIM model. The platform also includes AI tools that assist in comparing contractor quotes and helping builders make faster, more informed and data backed decisions. When a contractor successfully completes a project, they receive a digital certificate in the form of an NFT, which becomes part of their verifiable reputation and track record on the platform. Both builders and contractors have their own personalized dashboards to manage tasks, communicate updates, track progress and approve or verify completed work. By combining BIM, blockchain and AI in one easy to use system, ConQuote Connect offers a modern, transparent and trustworthy way to manage construction projects reducing disputes, saving time and improving industry collaboration.

Introduction

ConQuote Connect is a proposed smart construction procurement platform designed to improve trust, transparency, payment security, and efficiency between builders and contractors. It combines Building Information Modeling (BIM), blockchain, smart contracts, NFTs, and AI into one digital ecosystem.

1. Problem Addressed

The construction industry commonly faces:

• Unclear project scopes and requirements.
• Manual and inefficient procurement processes.
• Delayed or disputed milestone payments.
• Difficulty verifying project progress.
• Lack of trust and transparency between builders and contractors.
• Poor documentation of contractor performance.

ConQuote Connect addresses these problems by creating a single digital platform where project scope, quotations, progress, payments, and contractor reputation can be managed and verified.

2. Key Technologies

• BIM: Provides a visual 3D and data-driven representation of the construction project. It acts as a single source of truth for project scope and milestone verification.
• Blockchain: Provides secure, transparent, and tamper-resistant records of transactions.
• Smart Contracts: Create an escrow system that automatically releases payments when predefined construction milestones are verified and approved.
• NFT Certificates: Provide contractors with permanent, verifiable blockchain-based records of successful project completion and reputation.
• AI: Supports intelligent quotation comparison and decision-making during procurement.

3. Literature Review

Previous studies have demonstrated the potential of combining BIM and blockchain in construction. Research has shown that:

• 5D BIM and blockchain escrow can automate milestone-based payments.
• Scan-to-BIM and smart contracts can connect real-time construction-site data with payment triggers.
• BIM can serve as a single source of project information, while blockchain maintains immutable transaction records.
• Smart contracts can automate claims and help reduce disputes.
• Blockchain can improve transparency in construction supply chains by tracking materials and logistics.

ConQuote Connect builds upon this research by integrating BIM visualization, blockchain-based payments, AI quotation analysis, and blockchain-based contractor reputation into a single platform.

4. System Architecture

The system uses a multi-layered decentralized application (dApp) architecture:

• Next.js: Provides the web-based user interface.
• IFC.js: Enables interactive 3D BIM model visualization.
• Firebase Authentication: Handles user authentication and roles.
• Firebase Firestore: Stores project information, quotations, milestones, and related data.
• Gemini API/Genkit: Provides AI-based decision support.
• Polygon blockchain: Handles smart-contract escrow and NFT-based reputation records.
• MetaMask: Connects users' wallets to the Polygon blockchain and enables transaction signing.

5. Proposed System Workflow

The basic workflow is:

Builder creates project → BIM model defines scope → Contractors submit quotations → Builder evaluates quotations → Project milestones are established → Funds are secured in blockchain escrow → BIM/project progress is verified → Smart contract releases milestone payments → Contractor receives NFT completion certificate.

This process connects physical construction progress with financial transactions, reducing the possibility of payment disputes and improving accountability.

6. Results and Discussion

The implemented platform demonstrated that BIM, blockchain, and AI can be integrated effectively to support construction procurement.

The major features include:

• Landing Page: Introduces the platform and communicates its BIM and blockchain capabilities.
• Builder Dashboard: Allows builders to manage projects, quotations, milestones, and escrow status.
• Posted Project Page: Combines project information with an interactive IFC-based 3D BIM viewer for better scope understanding and milestone verification.
• Contractor Dashboard: Allows contractors to discover projects, submit quotations, and monitor bidding and awarded projects.
• Escrow Dashboard: Connects users to MetaMask and the Polygon blockchain, allowing secure and transparent milestone-based payments through smart contracts.
• NFT Certification: Provides contractors with an immutable digital record of successful project completion.

Overall Conclusion

ConQuote Connect combines BIM, AI, and blockchain to create a transparent and trustworthy construction procurement system. BIM improves project visualization and verification, AI assists quotation evaluation, blockchain provides secure and immutable records, and smart-contract escrow automates milestone payments. NFT certificates additionally provide contractors with verifiable digital reputations.

Conclusion

The ConQuote Connect project successfully demonstrates the capability to revolutionize construction procurement by tightly integrating BIM, Blockchain, and AI. The system effectively addresses the industry\'s critical issues of trust and transparency by establishing a workflow where BIM models act as the verifiable scope, Polygon smart contracts provide automated, secure escrow payments, and the Gemini AI delivers objective quotation comparison and risk assessment. By enforcing structured data submission and issuing NFT certificates for completed projects, ConQuote Connect bridges the gap between digital design, financial security, and contractor reputation, proving that smart technologies can significantly foster efficient collaboration, reduce disputes, and streamline the entire construction contract lifecycle.

References

Journal Paper [1] ZHANG Yan and FEI. Guangzheng, \"Overview of 3D Scene Viewpoints evaluation method\", Virtual Reality & Intelligent Hardware, vol. 1, no. 4, pp. 341-385, 2019. [2] Xiangyu Wang, \"Augmented Reality in Architecture and Design: Potentials and Challenges for Application\", International Journal of Architectural Computing, vol. 7, no. 02. [3] Y. Yorozu, M. Hirano, K. Oka and Y. Tagawa, \"Electron spectroscopy studies on magneto optical media and plastic substrate interface\", IEEE Transl. J. Magn. Japan, vol. 2, pp. 740-741, August 1987. Proceeding paper: [4] Shravani Aher, Roshani Avhad, Ekta Bhavsar, Om Pagare, Ms. Madhuri V. Malode, “Augmented Reality in Real Estate: Enhancing Property Visualization and Customer Experience”. [5] Stefan Seipel, Martin Andrée, Karolina Larsson, Jesper M. Paasch & Jenny Paulsson, “Visualization of 3D Property Data and Assessment of the Impact of Rendering Attributes”. [6] Nida Naeem, Irfan Ahmad Rana & Abdur Rehman Nasir, “Digital real estate: a review of the technologies and tools transforming the industry and society

Copyright

Copyright © 2026 Mr. Harshal Kadam, Mr. Mayur Prajapati, Mr. Amit Yadav, Prof. Sonali Karthik. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.