2. What is Masonry ?
Masonry is the building of structures from individual units laid in and bound
together by mortar; the term masonry can also refer to the units themselves.
The common materials of masonry construction
are brick, stone, marble, granite, limestone, cast stone, concrete
block, glass block, stucco, and tile. Masonry is generally a highly durable form of
construction. However, the materials used, the quality of the mortar and
workmanship, and the pattern in which the units are assembled can significantly
affect the durability of the overall masonry construction.
3. Types of Masonry walls
Based on load bearing
• Load bearing masonry walls.
• Non-load bearing masonry walls.
Based on construction
• Solid walls
• Veneered walls
• Reinforced walls
• Cavity walls
4. Load bearing masonry walls
A load-bearing wall (or bearing
wall) is a wall that bears a load
resting upon it by conducting its
weight to a foundation structure.
The materials most often used to
construct load-bearing walls in large
buildings are concrete, block,
or brick.
5. Non-Load Bearing Wall
Walls that are only intended to
support themselves and the weight
of the cladding or sheathings
attached.
Non load bearing walls provide no
structural support and may be
interior or exterior walls.
6. SOLID WALLS
Masonry units laid close together with all joints filled solidly with
mortar.
Solid walls are structurally bonded by metal ties, masonry
headers or by joint reinforcement.
Where solid masonry walls are used, insulation and mechanical
equipment are often installed within a furred space on the interior
side of the wall. Below grade, insulation is often placed on the
exterior side of the wall.
8. Internal Wall Insulation
Will slightly reduce the floor area of any rooms in which it is applied (the thickness
of the insulation is around 100mm)
Is disruptive, but can be done room by room
Requires skirting boards, door frames and external fittings to be removed and
reattached
Can make it hard to fix heavy items to inside walls – although special fixings are
available
is generally cheaper to install than external wall insulation
9.
10. External Wall Insulation
Can be applied without disruption to the household
Does not reduce the floor area of your home
Renews the appearance of outer walls
Improves weatherproofing and sound resistance.
Fills cracks and gaps in the brickwork, which will reduce draughts
Increases the life of your walls by protecting the brickwork
Is best installed at the same time as external refurbishment work to reduce the cost
Is not recommended if the outer walls are structurally unsound and cannot be repaired.
13. Reinforced masonry is any type of brick, concrete or other type
of masonry that is strengthened or fortified with the use of other building
materials to increase resistance to deterioration due to weight bearing or
other forms of stress
One of the most common examples of reinforced masonry involves exterior
walls that are created using concrete blocks or clay bricks. Along with the
blocks or bricks, steel rods are worked into the structure, often using some
type of vertical framework that aids in allowing the walls to bear up under its
own weight, and the weight of the connecting walls and floors within the
building.
14. The weaknesses of the masonry without reinforcement:
1. the sensitivity to cracks
2. the low flexural bearing capacity
Reinforcing in brickwork is applied for two causes: masonry is a quasibrittle material and is very
sensitive to cracking. Therefore, one part of the cracks can be prevented by using reinforcing bars or
mesh embedded in the bed joint, or the size of cracks can be significantly decreased. . The flexural
(tension) bearing capacity of masonry increases considerably with reinforcing.
15. Using reinforcement to prevent cracks horizontal bed joint reinforcement can be applied in the
following cases :
1. if temperature changes or moisture content variations occur, the bricks may dry out, and cracks will arise as a
consequence of shrinkage.
2. Strains resulting from differential settlement or
3. creep can cause big cracks.
4. At the corner of a building and at the cross junction cracks are very common due to the different strain of the
differently loaded wall sections. This type of cracks can be decreased with the reinforcing of the junction. In the the
consecutive layers of a T junction can be seen.
5. Infill walls in reinforced concrete frames can suffer damage due to the deflection of the floor.
6. In the place of concentrated load induction), tensile
stresses occur in the plane perpendicular to loading, which
can be handled by the bed joint reinforcement. Increasing the
load bearing capacity, the reinforcement improves the stiffness of the masonry, and it distributes the stresses almost
uniformly. For example by increasing the capacity of the masonry lintels or beams around openings, frameworks and
steelworks may be prevented. For that purposes, prefabricated reinforcement meshes and lintel hooks are available.
7. If the walls of cellars and retaining walls are unable to carry the loads from the pressure of the soil, it is recommended
to use vertical joint reinforcement; however, the implementation is more difficult.
16.
17. The Types of Reinforced
Masonry Walls
Depending on which materials are used, and how they are located, reinforced
masonry (RM) walls can be divided into the following classes:
•confined masonry
•reinforced cavity masonry
•reinforced solid masonry
•reinforced hollow unit masonry
•reinforced grouted masonry
•reinforced pocket type walls.
20. Veneered Masonry Wall
A brick veneer wall is constructed by having a non-structural external layer, usually
with bricks and it is
backed by an air cavity.
The innermost element of this type of wall is structural can consist of wood, metal
framing or masonry.
A brick veneer construction has many advantages over solid masonry. It shares
some of the advantages
of a cavity wall.
A brick veneer masonry wall is light weight, thermally efficient and can help in
reducing costs.
21.
22. Advantages
The airspace between the brick veneer wall and the structural element acts as a
drainage system.
The cavity can be insulated and this improves the thermal performance of the wall.
The structural element can be constructed first and this allows the rest of the
construction to proceed. The brick veneer can be completed simultaneously.
A brick veneer construction takes less time to complete than a solid masonry wall
which will give cost savings.
A veneer wall will weigh much less than a solid wall. Since the weight is less, the
cost of the foundation
and structural support can be reduced.
23.
24. Disadvantage
Masonry walls are durable and long lasting, but they
have one weak point: water penetration.
Solution
Flashing
27. INTRODUCTION
THE CAVITY WALL METHOD OF CONSTRUCTION WAS INTRODUCED IN
THE NORTHWEST EUROPE DURING THE 19th CENTURY AND GAINED
THE WIDESPREAD USE FROM 1920’S.
IN SOME EARLY EXAMPLES STONES WERE USED TO TIE THE TWO
LEAVES OF THE CAVITY WALLS TOGETHER.INITIALLY CAVITY WIDTHS
WERE EXTREMELY NARROW AND WERE PRIMARILY IMPLEMENTED
TO PREVENT THE PASSAGE OF MOISTURE INTO THE INTERIOR OF
THE BUILDING.
28. THE CAVITY WALLS CONSIST OF TWO SKINS SEPERATED
BY A HOLLOW SPACE (CAVITY).
THE SKINS ARE COMMONLY MASONRY SUCH AS BRICK OR
CONCRETE BLOCK. MASONRY IS AN ABSORBENT MATERIAL AND
THEREFORE WILL SLOWLY DRAW RAINWATER OR EVEN HUMIDITY
INTO THE WALL.
THE CAVITY SERVES AS A WAY TO DRAIN THIS WATER BACK OUT
THROUGH WEEP HOLES AT THE BASE OF THE WALL SYSTEM OR
ABOVE WINDOWS.
THE REASON CAVITY INSULATION KEEPS HEAT IN IS THAT THE
POLYMER AND AIR IN THE CAVITY ARE GOOD INSULATORS.
29. Construction work performed during the erection of stonework on buildin
gs and structures made of natural and artificial masonry materials.
Masonry work is a complex of processes that includes, in addition t
o the basic processes (the laying of brick or other stone in
mortar the delivery and laying out of the stone, and the smoot
hing of the mortar), related auxiliary processes (the erectionof scaf
folding and trestles and preparation of the materials at the constructio
n site).
Masonry is commonly used for the walls of buildings, retaining walls
and buildings. Brick and concrete block are the most common types of
masonry in use in industrialized nations and may be either weight-
bearing or a veneer. Concrete blocks, especially those with hollow
cores, offer various possibilities in masonry construction. They generally
provide great compressive strength, and are best suited to structures
with light transverse loading when the cores remain unfilled. Filling
some or all of the cores with concrete or concrete with steel
reinforcement (typically rebar) offers much greater tensile and lateral
strength to structures.
30. ADVANTAGES
The use of material such as bricks and stones can increase the thermal mass of a
building and can protect the building from fire.
Most types of masonry typically will not require painting and so can provide a
structure with reduced life-cycle costs.
Masonry is non-combustible product.
Masonry walls are more resistant to projectiles, such as debris from hurricanes or
tornadoes.
Masonry structures built in compression preferably with lime mortar can have a
useful life of more than 500 years as compared to 30 to 100 for structures of steel
or reinforced concrete.
Bricks are fire resisting material
DISADVANTAGES
Extreme weather, under certain circumstances, can cause degradation of masonry
due to expansion and contractions forces associated with freeze-thaw cycles.
Masonry tends to be heavy and must be built upon a strong foundation, such as
reinforced concrete, to avoid settling and cracking.
Other than concrete, masonry construction does not lend itself well to
mechanization, and requires more skilled labor than stick-framing.
Masonry consists of loose components and has a low tolerance to oscillation as
compared to other materials such as reinforced concrete, plastics, wood, or metals.
31. STRUCTURAL LIMITATIONS
Masonry has high compressive strength under vertical loads but has low tensile
strength (against twisting or stretching) unless reinforced. The tensile strength
of masonry walls can be increased by thickening the wall, or by building
masonry piers (vertical columns or ribs) at intervals. Where practical, steel
reinforcements such as wind posts can be added.
32. VENEER MASONRY
A masonry veneer wall consists of masonry units, usually clay-based bricks, installed on one or
both sides of a structurally independent wall usually constructed of wood or masonry. In this
context the brick masonry is primarily decorative, not structural. The brick veneer is generally
connected to the structural wall by brick ties (metal strips that are attached to the structural wall,
as well as the mortar joints of the brick veneer). There is typically an air gap between the brick
veneer and the structural wall. As clay-based brick is usually not completely waterproof, the
structural wall will often have a water-resistant surface (usually tar paper) and weep holes can
be left at the base of the brick veneer to drain moisture that accumulates inside the air gap.
Concrete blocks, real and cultured stones, and veneer adobe are sometimes used in a very
similar veneer fashion.
Most insulated buildings that utilize concrete block, brick, adobe, stone, veneers or some
combination thereof feature interior insulation in the form of fiberglass bats between wooden
wall studs or in the form of rigid insulation boards covered with plaster or drywall. In most
climates this insulation is much more effective on the exterior of the wall, allowing the building
interior to take advantage of the aforementioned thermal mass of the masonry. This technique
does, however, require some sort of weather-resistant exterior surface over the insulation and,
consequently, is generally more expensive.
33. DRY SET MASONRY
The strength of a masonry wall is not entirely dependent on the bond
between the building material and the mortar; the friction between the
interlocking blocks of masonry is often strong enough to provide a great deal
of strength on its own. The blocks sometimes have grooves or other surface
features added to enhance this interlocking, and some dry set masonry
structures forgo mortar altogether.
SEMI-INTERLOCKING
MASONRY
34. STONEWORK
Stone blocks used in masonry can be dressed or rough, though in both examples:
corners, door and window jambs, and similar areas are usually dressed. Stone masonry
utilizing dressed stones is known as ashlar masonry, whereas masonry using irregularly
shaped stones is known as rubble masonry. Both rubble and ashlar masonry can be laid
in coursed rows of even height through the careful selection or cutting of stones, but a
great deal of stone masonry is uncoursed.
Slipform stonemasonry produces a hybrid wall of reinforced concrete with a rubble stone
face.
Natural stone veneers over CMU, cast-in-place, or tilt-up concrete walls are widely used
to give the appearance of stone masonry.
Sometimes river rock of smooth oval-shaped stones is used as a veneer. This type of
material is not favored for solid masonry as it requires a great amount of mortar and can
lack intrinsic structural strength.
Manufactured-stone, or cultured stone, veneers are popular alternatives to natural stones.
Manufactured-stone veneers are typically made from concrete.
Natural stones from quarries around the world are sampled and recreated using molds,
aggregate, and colorfast pigments.
To the casual observer there may be no visual difference between veneers of natural and
manufactured stone.
35. BRICK
Solid brickwork is made of two or more wythes of bricks with the units running
horizontally (called stretcher bricks) bound together with bricks running transverse to
the wall (called "header" bricks). Each row of bricks is known as a course. The pattern
of headers and stretchers employed gives rise to different bonds such as the common
bond (with every sixth course composed of headers), the English bond, and
the Flemish bond (with alternating stretcher and header bricks present on every
course). Bonds can differ in strength and in insulating ability. Vertically staggered
bonds tend to be somewhat stronger and less prone to major cracking than a non-
staggered bond.
36. UNIFORMITY AND RUSTICITY
Masonry repair work done to a brick wall.
The wide selection of brick styles and types generally available in industrialized
nations allow much variety in the appearance of the final product. In buildings built
during the 1950s-1970s, a high degree of uniformity of brick and accuracy in
masonry was typical. In the period since then this style was thought to be too sterile,
so attempts were made to emulate older, rougher work. Some brick surfaces are
made to look particularly rustic by including burnt bricks, which have a darker color or
an irregular shape. Others may use antique salvage bricks, or new bricks may be
artificially aged by applying various surface treatments, such as tumbling. The
attempts at rusticity of the late 20th century have been carried forward by masons
specializing in a free, artistic style, where the courses are intentionally not straight,
instead weaving to form more organic impressions.
SERPENTINE MASONRY
A crinkle-crankle wall is a brick wall that follows a serpentine path, rather than a
straight line. This type of wall is more resistant to toppling than a straight wall; so
much so that it may be made of a single Wythe of unreinforced brick and so despite
its longer length may be more economical than a straight wall.
