resposibility

I have attached 2 pics. We had a fence number down during a storm this fence divides 2 houses. Waiting on deeds, but who would be responsible for fixing this fence, right side or left? My assumption was right as the posts are on that side.

I'm building a single storey extension to my house. I have an architect a separate structural engineer and a builder. My Building control officer has asked for: "Full construction specification for the extension showing compliance with Part B-P is required including the foul and surface water...