Automating Bill of Quantities: How LLMs Can Parse Engineering Drawings
Manual Bill of Quantities (BOQ) preparation remains one of the most time-intensive tasks in construction project management. This article investigates the feasibility of using Large Language Models (LLMs) to automate dimension extraction and material quantification from 2D engineering drawings. We examine the parsing pipeline — from image ingestion and OCR preprocessing to structured data output — and evaluate accuracy benchmarks against manually prepared BOQs for residential building projects. The findings suggest that LLM-based automation can reduce preparation time by up to 80% while maintaining consistency in quantity take-off operations, particularly for standardized drawing formats.