Old buildings are rarely square, level or plumb. Modeling them honestly means recording what is there, not what the drawings say should be there.
Uneven walls and floors
Agree a tolerance first. Within it, walls can be modeled straight; outside it, they follow the scan, with deviations noted.
Ornament and mouldings
Decide early how much ornament the model needs. Profiles can be traced from the point cloud and swept along their path, while very fine detail may stay in the scan as a reference.
Hidden areas
Voids, roof spaces and blocked rooms are marked as assumed or not surveyed, so nobody mistakes a guess for a measurement.
Conclusion
Accuracy and character are not in conflict. Clear tolerances, the right level of detail and honest notes give conservation teams a model they can rely on.
