I was actually just wondering the other day about a tree planted next to a building in this manner. I think it was 7 years old'ish. The building will need refinishing, painting or something. Even sooner now that it has a tree growing within inches of the siding. I'm sure that not everyone has planted and trained their tree right on the side of a building but in this instance, I predict issues right about the time the tree is fruiting well.
I would think like most practices, it has its places. I would enjoy being able to gather fruit when I am 80 without leaving the ground.
Thank you in advance if anyone would like to share a pic of their espalier.