From the 'You're A True Montrealer' game: doesn't matter how beautiful the building is, the first thought when seeing those windows is "the winter hydro bills!"
Do you know if there are any examples of "spite houses" in Montreal? They tend to be very narrow. Atlas Obscura has recently been featuring a few from elsewhere in the world.
If you mean they built a house which blocked the windows on the wall of the next house, yesCaron street If you're talking about very narrow structures, there are plenty of them here :Narrow Montreal