How do I raise the specific building in the game?

Hey exo..once a building is fully upgraded you cant change its type, but while youre upgrading them you can request new plans by tapping on the yellow hard hat and it gives you an option to request new plans..its random though.

Ive done it a few times if I notice too many identical buildings popping up in the same area. Ive also noticed that adding as much diversity in the layout of parks and other attractions in your city leads to better building diversity..hope that helps!

Cheers,

CJ