Our neighbor cut his down to about seven feet last fall. It's 15-20 feet tall now.

Builders here plant them right next to the houses and they get into water lines, etc. Not a lot of planning going on there!

I have one massive white flowering one that is too close to the house and was pruned last year, it is pretty much back to where it was. It is unstoppable.

I have another medium sized pink one that has had some rot but hangs in there year after year.

A third pink one took root last year and I let it grow. It is growing like gangbusters.