Preface:
It is easy to become distracted by new toolkits/workflows or competing software. This guide will briefly go over the most important requirements for prepping your model for a game engine
Non-Manifold Geometry:
These will produce errors in the game engine.
Below are 3 alternatives/ fixes to create proper Two-manifold geometry. The un-extruded faces are an intermediate shape. The extrusions are to show how this would look as a structure (architecture models).
Fix Three or more faces that share an edge:
Two or more faces share a single vertex but no edge:
Adjacent faces have opposite normals:
