An architectural scale model can be useful in a number of ways. For an organization it could be a model for display, perhaps for visitor orientation.
Where the building itself is an object of study, models can play an important role, allowing insight not easily afforded by traditional drawings.
The 3D CAD file used to create the model can itself be a useful tool and a free CAD viewer is available for those who do not posses the relevant software.
Created from an architect's plan for renovation or extension, a scale model can really help evaluate new building work.