BOND CLARITY

Building Elements:
BrickMasonry walls

INTRODUCTION
Masonry
Construction of building units bonded together
with mortar.
Brick masonry
Construction of brick units bonded together with
mortar.

Introduction
 Theterm “Masonry” isusedto indicated the art of building the
structuresin either StonesorBricks.
Theformer type iscalled “StoneMasonry”
Thelater type iscalled “Brick Masonry”
 The basic advantage of the masonry for the load bearing
structuresisthat it performs a variety of functionslike:
Affording architectural effect,
Granting fire and weather protection,
Providing acousticand thermal insulation,
Subdividing space,
Supporting loads, etc.

 Brick masonry is made up of bricks bonded together with mortar.
Therefore two essentialrequirements of brick masonryis:
Bricks:
 Bricksusedin masonrycanbe of two types
 Traditional / Country bricks (23 x 11.4 x 7.5 cm)
 Standard size(19 x 9 x 9 cm)
Some times bricks are also manufactured into special shapes and
sizes for architectural purposes e.g. copings, cornices, sting courses,
sloping walls etc.
Mortar:
 It is a mixture containing a binding agent (cement / lime),
aggregate and water thus acquiring stone like properties as a
result of hardening.
 Mortars are usedfor filling joints asa binder in stoneand brick
masonry,for preparation of decorative and protective plasters.

Basic definitions
 Course:
Acourseisa horizontal layer of bricks orstones.
 Stretcher:
Stretcheristhe longer face of the brick (19 cmx 9cm)
A course of bricks in which all the bricks are laid as stretches on facing is
knownasa stretchercourseor stretchingcourse.
 Header:
Header isthe shorterface of the brick (9cmx 9cm)
Acourseof bricks in whichall the bricks are laid asheadersonthef
acingis
knownasheader courseor headingcourse.
 Bed:
It isthe lower surface of brickswhenlaid flat and thusit isperpendiculart
o the
line of pressure. It indicates the lower surface of bricks or stones in each
course.
 Arrises:
Arrisesare the edges formed by the intersectionof plane surfacesof a brick.
Theyshouldbe sharp, square and free from damage.

Basic definitions
 Lap:
It isthehorizontal distancebetweenthevertical jointsof successivebrick
courses.
 Perpend:
Perpend is an imaginary vertical line which includes the vertical joint
separating two adjoining bricks.
 Quoin:
Quoin is a corner or their external angle on the face side of a wall.
Generally quoin’s are at right angles, but in some cases their angles can
be greater than90o also.
 Bed joints:
Bedjoints are horizontal layer of mortar uponwhichbricksare laid.
 Racking back:
It isthe termination of a wall in a stepped fashion.
 T
ooting:
It is the termination of the wall in sucha fashion that each alternate course
at the end projects, in order to provide adequate bond if the wall is
continuedhorizontally at a later stage.

Basic definitions
 Quoin brick:
Thebrick, whichformsthe external corner of a wall isknowna
s
“Quoin brick”.
 Quoin header:
A corner header, in the face of wall, whichisa stretcher in t
h
e
• side wall isknownas“Quoinheader”.
 Quoin stretcher:
Acorner stretcher in the face of a wall, whichisheader int
h
e
• side wall isknownas“Quoin stretcher”

Basic definitions
 Bat:
It isthe portion of brick cutacrossthe width and hencea bat is
smaller in length than the full brick.
The following are SOME OF the types of bats used in brick
masonry, which are defined by considering its relation to the
length of a brick
 Half bat: If the length of brick isequal to half the length of the
original brick, it isknownashalfbat.
 Three-quarters bat: If the length of the brick isequal to three
quarters of the length.
 Bevelled bat: If the bat hasitswidth bevelled thenit is called
bevelled bat.
 Bullnose: Abrick with a rounded angle istermed asbull nose.

Pictureof various types of Bat
Quarter bat

Basic definitions
 Closer: A piece of brick which is used to close up the bond at
the end of brick courses, is known as closer and helps in
preventingthejointsofsuccessivecoursestocomeinavertical line.
Generally the closer is not specially moulded. Butit is prepared
by the masonwith the edge of trowel.
 Thefollowing are someof the types of closure
Queen closer: Thisis obtained by cutting the brick longitudinally i
n two
equal parts. It can also be made from two quarter bricks, known as the
quarter closers, to minimize the wastage of bricks. A queen closure is
placed near the quoinheader to obtain the necessarylap.
King closer: Thisis obtained by cutting a triangular portion of t
h
e brick
such that half of header and half of stretcher are obtained on the
adjoining cut faces. A king closure is used near the door and window
openingsto get satisfactory arrangement of mortar joints.

BEVELED
CLOSER
It is a form of king closer in which the whole length of the
brick (i.e. stretcher face) is chamfered or beveled in such a
way that half width is maintained at one end and full
width ismaintained at the other end.
MITRED CLOSER
It is a portion of a brick whose one end is cut splayed or
mitred for full width. The angle of splay may vary from
450 to 600. Thus one longer face of the mitred closer is of
full length of the brick while the other longer face is
smaller in length.

Pictureof various types of Closures

Elevation of wall showing various
terminology

15
Basic Brickwork Terminology
Bed
Joint
Head
Joint
Course -
horizontal
layer of brick

Half
bat
Queen
closer
King
closer

Masonry Joints
Flush
Racked
Concave
Struck
Weathered
Concave
Vee
Concave Joints
Raked Joints

 English Bond
 Flemish Bond
 Stretching Bond
Heading Bond
Garden Wall Bond
Facing Bond
Raking Bond
Dutch Bond
English Cross-Bond
Zig-Zag Bond
Silverlock’s bond
Types of Bond

Why bond is necessary ???
• Eliminates continuous vertical joints
• Imparts strength to the masonry
• Defective arrangement reduces strength &
durability
• A wall having continuous vertical joints does
not act as homogeneous mass

STRECTCHER BOND
HEADER BOND
ENGLISH BOND
FLEMISH BOND
FACING BOND
ZIG ZAG BOND

Bonds
 Since masonry consists of a large number of individual
units jointed together with mortar soas to form one mass, it
is necessary to lay the units in sucha way that, under load,
the unitsact jointly.
 Themostimportant rule to be observed in this connection is
that vertical cross-joints in any course should be staggered
and these should not be nearer than a quarter of brick
length from thosein the coursebelow or above that course.

Typesof Bonds in Brickmasonry
 Thereare a numberof brick laying arrangements in vogue-called
‘bonds’, of whichthosecommonlyusedare:
‘Stretcher bond’,
‘Header bond’,
‘English bond’,
‘Double & Single Flemish bond’,
Garden-wall bond,
 English garden wall bond
 Flemish garden wall bond
Raking bond,
 Herring bone bond
 Diagonal bond
English cross bond and
Dutch bond.

Stretcherbond
 Inthistype of bond, all the bricks are arranged in the stretcher
courses.
 Thestretcherbondisusefulfor one-brick partition walls; cavity
walls asthereare noheadersin such walls.
 As this bond does not develop proper internal bond, it should
not be used for walls having thickness greater than one-brick
wall.
 Stretcher bond in the brick isthe simplest repeating pattern.

Isometricview,Elevation and plan of
Stretcherbond

Header bond
 In this type of bond, all the bricks are arranged in header
courses.
 The overlap is usually kept equal to half the width of brick and
it is achieved by using three-quarters brickbats in each
alternate coursesasquoins.
 This bond does not have strength to transmit in the direction of
length of wall. Henceit isnot suitable for load bearing walls.
 However this bond is used for curved surfaces in brickwork
because stretchers, if used for curved surfaces, would project
beyondthefaceof wall.

Isometricview,Elevation and plan of
Header bond

English Bond
 Inthisbond, bricks in thefacing are laid asalternate header
and stretcher courses.
 The header course is commenced with a quoin header followed
by a queen closer and continued with successive headers. The
stretcher course is formed of stretchers, having a minimum lap
of onequarter brick length.
 This bond is considered to give the best strength in masonry
and is mostly adopted in all load bearing masonry that is to be
plastered over.
 Inthis bond whenthe wall is only one brick thick, one face is fair
and even, while the other face may be uneven due to slight
variations in length and breadth of units.

Contd…
 If the wall thickness is an even multiple of half-brick, the same
course shows headers or stretchers in both front and back
elevations. But if the wall thickness is an uneven multiple of half-
brick, a courseshowingstretcher ontheface elevation and header
on the back elevation and vice versa is seen.
 Aheadercourseshouldneverstat witha queencloseras it is liable
to get displacedin this position.
 Thequeenclosersare not required in thestretcher courses.
 In the stretcher course, the stretchers have a minimum lap of one-
fourth of their length overthe headers.
 For walls having thickness of two bricks or more, the bricks are
laid as stretchers or headers only on the face courses of the wall.
Theinteriorfillingisdoneentirelywiththeheaders.

Isometric view of English Bond
1 brickthick wall
Queen
Closer
Header
Course
Stretcher
Course
Header
Course
Stretcher
Course
Directionof
Elevation view

Elevationof1Brickthick
English
bond

Plan for1brickthickwall (English
Bond)
H= Header
S= Stretcher
Q = Queencloser
Face
Back
Face
Back

Isometricview of English Bond
𝟏
𝟐
1 thickbrick wall
Directionof
Elevation view
Header
Course
Stretcher
Course
Quarter
Queen closer

Elevation of 1
𝟏
Brick thick
𝟐
English bond

Plan of 1–1/2Brick thick
Englishbond
Quarter Queen
closer (or)
Quarter Bat
Queen
closer
Header
Stretcher

Elevation of 1-1/2 Brickthick
Englishbond
Stopped
end

Introduction
 In every course, headers and stretchers are placed
alternatively.
 The queen closer is put next to the quoin header in
alternate coursesto develop the face lap.
 Every header is centrally supported over a stretcher
below it.
 TheFlemishbond maybe divided into two groups:
DoubleFlemishbond
SingleFlemishbond

Double Flemish bond
 Indouble Flemish bond, the headersandstretchersareplaced
alternatively in front aswell astheback elevations.
 For this type of bond, the half bats and three-quarter bats will
have to be used for wall thickness equal to odd number of half
bricks.
 For wall thickness equal to even number of half bricks, no bats
will be required and a stretcher or header will come out as
stretcher or a header in the same course in front as well as back
elevations.
 Thisbond gives betterappearance than theEnglish bond. But it
is not so strong as the English bond as it contains more number
of stretchers.

Elevation of Double FlemishBond
Stopped
end

Plan of 1 Brickthick
Double Flemish bond

Isometric view of 1
𝟐
𝟏
Brick thick
Double Flemish bond

Plan of 1
𝟏
Brick thick
𝟐
Double Flemish bond

Single Flemish bond
 In Single Flemish bond, the face elevation is of Flemishbond
and thefilling aswell asbacking are of English bond.
 Thus, in this type of bond, an attempt is made to combine the
strength of the English bond with the appearance of the
Flemishbond. Thistype of bond is usedwhenexpensive bricks are
usedfor thefacework.
 But in order to construct this bond, a wall of minimum
𝟐
thickness 1𝟏
bricks is required.

Isometric view of 1
𝟏
Brick thick
𝟐
Single Flemish Bond

Front/ Face elevation
(i.e.itresemblesDouble Flemish bond)
Stopped
end

Back Elevation [Pictorial representation only]
(i.e.itresembles English bond)
Stopped
end

Plan showing Flemish bond,English
bond appearance in Single Flemish bond

Plan of 1𝟏
Brick thick
𝟐
Single Flemish bond
Stopped
end

Comparison of English bond vs Flemishbond
English bond Flemish bond
Compact and stronger for walls
especially of thickness more than
1½ bricks.
Less Stronger & compact
than English bond.
Lesspleasing appearance More attractive & pleasing
Costismore Slightly Economical. (as it uses
broken brick bats, although it
requires some extra mortar for
additional joints)
No strict supervision required. Good Workmanship and
careful supervision
required.

Picturesof Various types of bonds
Stretcherbond

Advantages of brick masonry
The brick masonry is cheaper as compared to
stone masonry.
Bonding strength is very good.
In brick work , the mortar joints are thin and
hence the structure becomes more durable.
No complicated lifting devices are necessary in
brick work.
Brick work can be done by the less skilled
labours also.
In Brick work good quality of bricks posses
good fire resistance.
Due to regular size of bricks they are
easy to handle.

Defects in brick masonry
 Sulphate attack
Sulphate salts present in bricks work react with alumina
content of cement .
It occur in boundary walls
 Crystallization of salts from bricks
Occur in masonry made out of brick which contain excessive
soluble salts
This phenomenon is also known as efflorescence.
 Corrosion of embedded iron or steel
Iron or steel embedded in brick work gets corroded in the
presence of dampness
On corrosion the metal expands in volume and tends to
crack the brick work.

English bond
 In general practice this type of bond is used.
 It consists of alternate courses of headers and
stretchers .
 Considered as strongest bond in brick work
 For breaking vertical joints queen closer is placed after first
header
 Heading course should never start with a queen closer
 Stretchers should have a minimum lap of ¼ their length
over the header
 Even number of half brick walls present same
appearance
 For odd number we see stretcher on one face and header on
other
 In thick walls, the middle portion is entirely filled with
header

Header course
Stretchers course
Queen closer
ISOMETRIC VIEW OF
ENGLISH BOND

Flemish bond
•Each course consists alternate
headers and stretchers.
•Not as strong as English bond.
•Alternate course starts with a header
at the corner.
•For breaking of vertical joints , closers
are inserted in alternate courses next
to the quoin header.

ISOMETRIC VIEW
OF FLEMISH
BOND
Heade
r
Stretche
r

FLEMISH BOND
 Every course consists of header and stretcher
 Header are centered over stretcher
 Every alternate course start with header
 Closers are inserted next to the quoin

 Single flemish bond:
 Combination of english and flemish bond
 In a course, facing is flemish and backing is
english
 Cannot be adopted in walls having thickness
less than one and half brick
 Provided for the attractive appearance of the
flemish bond

 Double Flemish bond:
 Each course presents the same appearance both in the
face and back of the wall
 Every course consists of headers and stretchers
alternately
 Best suited for consideration of economy and
appearance
 This type of bonding is comparatively weaker than
English bond

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