Civil Engineering Reference
In-Depth Information
Chapter 5
External doors,
thresholds and shutters
Although external doors, as part of
the external envelope of buildings, in
theory should conform as nearly as
possible to the performance
requirements of the remainder of the
envelope, the extra requirements of
access and the wear and tear that this
involves have inevitably tended to
make them more of a compromise
than that of the wall in which they are
situated (Figure 5.1). Many have
been compromises between lightness
in weight, for ease in opening, and
robustness to resist unauthorised
entry.
This chapter deals with all kinds of
external doors used for both
pedestrian and vehicle access, and
with shutters and gates which provide
additional protection to both doors
and windows against unauthorised
access.
Figure 5.1
Glazed entrance (and emergency exit) doors at a school in the days before security
became a real issue
