First thing I notice is that a 2m high brick wall in London (but
nowhere else) requires building regs approval.

Whilst that was true in 1984, I can't find any current reference
saying it's still the case, and it's not mentioned on any of the
London Council's Building Control websites I looked at.
Anyone know if it's still the case?

While the planning portal
(http://www.planningportal.gov.uk/per...ceswallsgates/
) states simply that "Fences, walls and gates do not require building
regulation approval." the City and Inner London Boros. may disagree.
Several of them still refer to the need for an application under s.30 of
the 1939 Act dealing with "(although it's been brought within the
Building (Inner London) Regulations 1985 and heaven knows how they have
been amended). Eg

http://www.rbkc.gov.uk/planningandco...ildingact.aspx
"Certain special or temporary structures, e.g. flag poles, flue pipes,
temporary stands for special events, freestanding boundary walls greater
than 1.83 metres in height, require a consent to their erection and
retention."

http://www.islington.gov.uk/environm...structures.asp
conveniently gives the text of the legislation


--
Robin
PM may be sent to rbw0{at}hotmail{dot}com