Retaining wall distances

[crashy]

I had a look at the legislation but it's not clear to me:
How close to a buildings foundation can you put a retaining wall?
How close to a boundary can you put a retaining wall?
How close to another retaining wall can you put a retaining wall?
I want to excavate an area between 2 houses, the total height is about 2.2m but since the limit without a consent is 1.5m, I plan to stagger the levels and probably do two retaining walls 1.1m high.

Also if a block wall has 1.5m earth behind it, can you just excavate the earth without issue?

[mak]

You probably need an engineer to answer those questions. But I can tell you what I think I know.
How close to a buildings foundation can you put a retaining wall?
If you took a 45 degree line down from the bottom of the house foundations and the foundations of the retaining wall crossed that line then a building consent would be needed.
How close to another retaining wall can you put a retaining wall?
Same answer as above.
Mak