Accurate as-built information is required to operate, maintain, and adapt existing buildings. Scan-to-BIM has become a feasible approach for collecting and modelling 3D as-built information and has three phases: (1) scanning, (2) registration, and (3) modelling. This paper focuses on the modelling phase, which can currently be conducted either manually or semi-automatically. As-built conditions of a building are surveyed, and the geometry is modeled in a series of modelling scenarios. For each trial, geometric dimensions of the BIMs are compared to ground truth dimensions. This paper assesses the impact of levels of automation and modeller training on the accuracy and precision of generated BIMs. Quantitative models are developed for modelling scenarios using empirical datasets. Lastly, the impacts of degrees of accuracy are discussed. This study provides insight into the dimensional certainty of BIMs generated by Scan-to-BIM and helps decision-makers assess the risk of decisions made based on this information.

操作，维护和改造现有建筑物需要准确的竣工信息。扫描到BIM已成为收集和建模3D竣工信息的可行方法，它具有三个阶段：（1）扫描，（2）注册和（3）建模。本文着重于建模阶段，目前可以手动或半自动进行。测量建筑物的建成状态，并在一系列建模方案中对几何进行建模。对于每个试验，将BIM的几何尺寸与地面真实尺寸进行比较。本文评估了自动化和建模师培训水平对生成的BIM的准确性和精确性的影响。开发了用于使用经验数据集建模方案的定量模型。最后，讨论了精确度的影响。