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Class Day Twelve
Chapter 8
Brick Masonry
History of Brick Masonry
A No one really knows the age of brick masonry.
B Common sense would dictate that the lack of
construction materials for shelter in lands where
no natural stone was available, would lead to
innovations with whatever material is at hand
C Where there was land there was soil, and if
there was water there was mud. And soil particles
stick together and form a hard mass when the sun
dries the moisture.
D Mud bricks were molded by hand and allowed
to dry in the sun, and stockpiled for future use.
Small units were easily handled.
E Mud bricks were stacked with mud mortar,
which varied in thickness to accommodate
irregular shapes.
F It was learned that the best bricks were made
of soil that had very tiny particles and became
sticky when wet. The material we call clay.
G In the southwest regions of North America,
“Adobe” bricks were made of a clay that has come
to be known as adobe clay, which was particularly
good for making mud bricks. Adobe was further
strengthened by adding short strands of straw to
the mix. Adobe bricks are still made and used
today.
H Consistency of size did not become prevalent
until units were cast into molds, which greatly
facilitated ease of assembly.
I
The industrial revolution of the late 1800s
brought about the firing of masonry in kilns, which
made the units very hard and strong.
J In the early 1900s other materials surpassed
brick in use because of strength requirements for
buildings too tall and heavy to be supported by a
“mass” type wall.
K But brick has and intimacy about it that
remains a warm and friendly material for use in
construction of residences and office buildings
BRICK MORTAR
A Mortar is a vital part of brick construction.
B As bricks are made of clay, then fired in a
furnace to remove the moisture and make them
hard, they are impossible to make in exact,
consistent size – but in modern day it is close.
C In early times, mortar was used as a cushion to
align the assembly process to maintain square
and plumb in a structure. Additional strength in
the mortar mix was not necessary because it was
made of the same material as brick.
D But since fired bricks are much stronger than
the original sun-dried clay, the strength of mortar
was improved to make stronger buildings.
E With the development of natural cement for the
manufacture of concrete, it became a natural
matrix for masonry mortar.
F Mortar is a mix much like concrete; which
consists of stone aggregates held together by a
matrix. In the case of concrete, that consists of a
gradation of large rocks, smaller rocks, and still
smaller particles (sand) – all mixed consistently
and held together by a paste of cement and water,
which hardens by a chemical process called
hydration.
G Masonry mortar is a mixture of sand, cement,
and water, with the addition of lime to lend
smoothness and workability to the mix.
Mortar Functions
Provides for full bearing of weight
Maintains the strength of the masonry wall
Seals against moisture and vermin
Bonds the masonry units together
It should be a part of the
aesthetic value of a
building.
MAKING BRICKS
A Early molding of bricks was done by shaping a
mass of mud by hand.
B Then individual single molds made of wood
increased production and consistency of size.
C Then multiple molds made of wood increased
production even more.
D Today, very sophisticated methods exist for
shaping bricks by extruding clay through a steel
form, then cutting to individual units with wire.
Wood molds for making brick
E The making of bricks became more
sophisticated with units extruded and wire cut,
then fired in gas kilns. Production and quality of
units increased tremendously.
F The color of bricks up until approximately 20
years ago depended upon the color of clay, which
was found in large deposits in the ground.
G Constant use of brick as a veneer in residential
and commercial construction as population grew,
led to depletion of consistent color clay deposits.
H Now, nearly all brick used in residential
construction are made of any clay, but given their
color by a slurry mix that is applied to the units
before firing.
Basic types of brick:
Common brick: Units made of clay where
color and surface finish are not a factor,
because of use as a “backup” structural
material in an area where it will never be seen.
Face brick: Units made where appearance is
the main consideration. Face brick for
commercial use is still made with specific
colors of clay.
Special bricks may be made for specific
purposes. Should an Architect desire a
special shape to be used in creating an
unusual desired effect in a design, brick
companies will custom make the units.
Fire brick is made of a specific type of white
clay, with special additives for use in the
firebox of fireplaces, ovens, kilns, and other
firing mechanisms.
Bricks, generally are made with holes (except
fire brick) to reduce the weight of material not
needed for structure, and to provide a method
for additional adherence of mortar.
Bricks made of the same material as concrete
masonry units are available on a limited
basis, but have never been accepted for
widespread use.
BRICK SHAPES AND SIZES
The text shows a chart with 12 sizes of bricks, but
all available sizes and shapes are not listed.
Two shapes of brick are commonly used, but
many others are made for specific purpose.
Modular Brick – nominally lay 8” long, 4”
thick, & 3 courses high = 8”. Texas Tech uses
modular brick. For use where strength and
appearance is important.
King Size Brick – nominally lay 10” long, 3”
thick, & 2 ½” high. For use as a veneer where
economy is the main concern.
Eight modular size bricks are required to lay
one square foot of surface wall, but it takes only
5.4 king size bricks for the same area. So, king
size brick are made strictly for economy.
Bricks shapes made for appearance:
Roman brick – basically 12” long, 4” thick, 1
½” high.
Norman brick – basically 12” long, 4” thick, 3
courses = 8” high.
Big Johns – basically 12” long, 4” thick, 4”
high.
 BRICK ARRANGEMENT TERMINOLOGY
 A Bricks are laid in a variety of arrangements,
mostly today for the sake of appearance. In earlier
times when a wall consisted of several layers
thickness, bricks were turned endways through
the wall for structural bond. Named patterns
evolved in the process, such as English bond,
Flemish bond, etc.
 B Common course pattern for structure and
appearance:
Stretcher –
Bricks laid flat end to end.
Soldier –
Laid vertically so the outside
long edge shows.
Rowlock Laid so the end shows,
vertically.
Header – Laid so the end shows, horizontally
Basic Brickwork Terminology
Head
Joint
Bed
Joint
Course - horizontal layer of brick
Brickwork Terminology
Header - Bonds two wythes together
Wythe: vertical layer 1 unit thick
Rowlock laid on face,
end visible
Stretcher - long dimension horizontal
& face parallel to the wall
Soldier - Laid on its end, face parallel
Brick Masonry - Sizes and Shapes
There is No standard size
Normal coursing - 3 modular bricks = 8”
Larger sizes available
Custom shapes & colors are available
Masonry Joints
Weathered
Concave
Various tools are used
to treat the surface
finish of mortar joints.
Vee
Flush
Raked
Stripped
Struck
Some are done to
repel water, but most
are done for
appearance.
Concave joints done primarily for weather proofing
Raked joints are made primarily for appearance
In the category of the Earnheardts, Emmet Smith, Tiger
Woods, etc, this man is the world champion bricklayer of
2004. In a contest in Las Vegas, Bob Bol laid 765 bricks in
ONE HOUR. That’s 12.75 bricks per minute – or one brick
every 5 seconds.
He won a prize of $2,000.