  This paper presents a new algorithm for filling holes in Level of Detail 2
(LoD2) building mesh models, addressing the challenges posed by geometric
inaccuracies and topological errors. Unlike traditional methods that often
alter the original geometric structure or impose stringent input requirements,
our approach preserves the integrity of the original model while effectively
managing a range of topological errors. The algorithm operates in three
distinct phases: (1) pre-processing, which addresses topological errors and
identifies pseudo-holes; (2) detecting and extracting complete border rings of
holes; and (3) remeshing, aimed at reconstructing the complete geometric
surface. Our method demonstrates superior performance compared to related work
in filling holes in building mesh models, achieving both uniform local geometry
around the holes and structural completeness. Comparative experiments with
established methods demonstrate our algorithm's effectiveness in delivering
more complete and geometrically consistent hole-filling results, albeit with a
slight trade-off in efficiency. The paper also identifies challenges in
handling certain complex scenarios and outlines future directions for research,
including the pursuit of a comprehensive repair goal for LoD2 models to achieve
watertight 2-manifold models with correctly oriented normals. Our source code
is available at
https://github.com/tudelft3d/Automatic-Repair-of-LoD2-Building-Models.git
