Hi,
As I understand it from a previous thread a week or so back, it is
permissable to build a garage extension right up to the boundary between
neighbouring properties and the foundations can actually cross over.
The idea being to eliminate unsightly gaps between extensions built side
by side. If this is the case, what happens when the second person to
build then wants to build up to the boundary too? Does his wall bear on
those original foundations? If so, what happens if those foundations
are only suitable for a single story and the second person wants to
build higher? (I may be in a similar situation sometime. The original
thread fizzled out.)

Rockydell