I own a semi-detached house 10m tall. A large garage on the detached side shares the bottom 2m of the wall. It belongs to the neighbours, who will build a house to replace the garage. Is the whole side wall considered a party wall, or only the bottom 2m?
I would say all of the 10m wall based on the definition given at s.20 of the Party Wall Act 1996:
"party wall” means—
(a) a wall which forms part of a building and stands on lands of different owners to a greater extent than the projection of any artificially formed support on which the wall rests; and
(b) so much of a wall not being a wall referred to in paragraph (a) above as separates buildings belonging to different owners;
NB as per s.22(4), the 1996 Act extends to England and Wales only.