Take a look here. Loads 70 MB of JSON, so be patient, please :)
What's in here?
You'll get a pretty, colourful model that you can zoom into, turn around and bask in its gorgeousness. Looks like this:
Grundlage: Geodaten © GIS-ZH
and you should be good. But I'm not a lawyer and not liable for anything you do with this data or that results from your use of that data.