(Facade of the Church of Santa Stefano,
Here's a much grander version from the 13th century. Note especially the horizontal stripes on the tall bell tower behind the cathedral.
I'm wondering if I could plausibly work a striped pattern like this into the house of my heroine's father, who is a rich silk merchant in Venice? For now I'm just researching and taking notes. I'll make a decision on this in the second draft of my current WIP. If you'd like to read more about striped buildings in Italy, there's an interesting article on the internet called "Facades and Stripes: An Account of Striped Facades from Medieval Italian Churches to the Architecture of Mario Botta." You can read the article here.