all images via Archinect
It appears to be a renovation and extension that gets to break a few zoning rules because of an existing wall that enclosed the yard.
The stair is interesting. I thought at first that it was some kind of alternating tread stair but really he has only cut out half the riser and none of the tread, so functionally it is a normal stair.
Lovely courtyard, and another demonstration that sometimes, you are far better off working with what you have than you are building from scratch. You can get grandfathered around zoning rules and you can get an interesting mix of new and old.
More at Archinect
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