On a British gardening blog. Good neighbourliness involves the two neighbours discussing and agreeing this sort of thing before it happens. In Kapiti a fence over 2.5 metres in height (not on a street frontage) requires council consent — and an addition like this is pretty close to what you could consider an increase in the height of the fence.
You may not be interested in the Fence Wars of our neighbours, but as it was only yesterday that I mentioned it, and there were ‘developments’ today, I thought some of you might be curious. Sometime early this morning (and perhaps under cover of darkness…?!) a trellis was attached to the bare fence posts and covered with fine mesh, the same kind of mesh that had been attached to our boundary (next to the cutting beds and fruit cage) a day or so after I had the audacity to make myself known to the young man living there when he walked past on the other side of the fence…
via For Your Information: Fence Wars — Rambling in the Garden