Introduction
Revised Building Regulations for England & Wales, related, in part, to the structural design of buildings to resist accidental damage,
have recently been published together with the relevant Approved Document giving guidance on accidental damage design. Although
the changes are not quite so far reaching as they appear to be at first sight, they do have implications for the design of traditional
masonry buildings. This Technical Note gives guidance on the design of masonry structures to be in accordance with the new
disproportionate collapse requirements of the Regulations.
Revised Building Regulations
New requirements for dealing with accidental damage came into force on 1st December 2004, when Building Regulation A3
was changed. Approved Document A to the Building Regulations has been revised to give guidance on the manner in which the
new A3 can be satisfied, but it is not specific to any material or form of construction. BS 5628: Part 1: 1992, in clause 37, gives
guidance suitable for masonry buildings, in order to satisfy the accidental damage rules that applied prior to 1st December 2004.
Note: BS 5628 will be revised to take into