Civil Engineering Reference
In-Depth Information
A major concern which affects the efficiency of cavity con-
struction is the carelessness of bricklayers who allow mortar
droppings to fall to the base of the cavity during wall construc-
tion. This should not occur but if it does, unwanted material
can be cleared out using the technique shown in
Figure 14.2
.
Brick suppliers such as Ibstock (www.ibstock.com) supply
excellent information sheets indicating brick dimensions and
quantities to cover specific areas.
STRETCHER BOND
HEADER BOND
Common bricks
Although the term
common brick
is frequently used in the indus-
try, it finds no specific resonance in British Standards. They are
simply bricks of sufficient strength and durability to be used in
situations where they are not permanently exposed to view.
ENGLISH BOND
FLEMISH BOND
Facing bricks
These are bricks that exhibit a pleasant appearance when used
in situations where they are permanently on view. Many differ-
ent types are available and can be viewed on display at brick-
makers' premises or in trade catalogues. Where appearance is
important, practitioners should be encouraged to arrange for
display panels to be constructed before making a final decision
on types of facing brick.
FLEMISH GARDEN WALL OR SUSSEX BOND
Engineering bricks
This is a term of convenience in the UK but does not appear in
British or European Standards. However the National Annexe to
BS EN 771-1 does use the term. Generally speaking these bricks
have lower water absorption but higher compressive strength
characteristics than other bricks and are suitable for use in aggres-
sive environments. Typical uses are for damp proof courses or
at the bases of freestanding masonry retaining walls in order to
eliminate the plane of weakness caused by sheet material damp
proof courses. Best practice suggests the use of two courses in
these circumstances. BS 5628-3:2005 gives guidance on the use
of these and other bricks for use as damp proof courses.
ENGLISH GARDEN WALL BOND
MONK BOND
Figure 14.1 Brick bonding (Doran 2009). Reproduced courtesy of
Whittles Publishing
perhaps where lateral loading is to be resisted, masonry may
be pre-stressed.
Bricks and blocks may be solid or perforated (to reduce
weight and/or increase thermal properties). The compressive
strength of bricks varies enormously from about 7 N/mm
2
to
well in excess of 100 N/mm
2
for clay bricks and 21 N/mm
2
to
60 N/mm
2
for calcium silicate and concrete bricks.
Cavity wall construction is usually used to enhance insu-
lation. Such walling may consist of
brick and brick
or
brick
and block
. The two leaves should be tied together with non-
ferrous ties to increase stability and load-bearing capacity.
With the need to better conserve energy a number of systems
for increasing the thermal capacity of cavity walls a number of
systems have arisen which include:
Other bricks
The range of other available bricks is very wide. Their descrip-
tions are often related to the process of manufacture and
include:
extruded wire-cut
■
pressed
■
soft-mud
■
stock
■
hand-made
■
specials
■
stiff plastic
■
The inclusion of compressed glass-fibre batts within the cavity
■
semi-dry
■
during construction.
A retrofitting injection of polystyrene pellets or foam into the cav-
clamp
■
■
ity through holes drilled in the external skin.
burnt.
■
