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june 2012 site stimulation for qsd 132
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Faculty of Architecture, Planning and Surveying
QSD 132 – Construction Technologies I
Assignment 1 – Site Stimulation
Brickwork
Name: Dahlia Binti Ab Aziz
Student ID: 2012611132
Class: AP1141FC
Date Of Submission: 10 September 2012
Lecturer’s Name: Miss Lina INTRODUCTION
The video shows a single specified residential house in a suburban area. The situation can be
referred and similarise with a long Belgium block of 2008, custom built home sit on an oversized lot in
Riverbank, California. Generally describe the house with simple specification such as the gardens have
been professionally landscaped. The lovely home offers such amenities as covered front and rear porches
even when flagstone. An outdoor front porch and grill also included as with an elegant pool house with full
bath. The house consists of six bedrooms with 8 and half bathroom. The house itself is 7,203 squarefeet
while the area of the residence is about 39,639 squarefeet and that means 0.91 acres in total. It is suitable
for a single family with an attached garage and a lovely traditional fireplace.
The video showed how the brick of the house was layered and all the procedures required for it.
The technique for the brickwork was explained and visualized. The process of a wall was gradually shown
from a brick into a wall along with the use of mortar, flashing and weep mole. From the video, it is obviously
state on what is the technique is used for the wall and the way it is layered. It is shown on the use of wall
ties.
Brickwork is large field that when it is combined together with various selections could create
magnificent monument although it is only a wall. What more is it is when a combination was create right it
could stand tall with no earthquake could make it crumble and fall. It is proven with the standing of The
Great Wall of China and The Pyramid of Giza. The Ancient Egyptians also used sun dried mud bricks as
building materials, evidence of which can still be seen today at ruins such as Harappa Buhen and Mohenjo-
daro. Paintings on the tomb walls of Thebes portray slaves mixing, tempering and carrying clay for the sun
dried bricks. These bricks also consisted of a 4:2:1 ratio which enabled them to be laid more easily.
Although great thing could achieve, a wrong combination could crumble and crack with only wind or water
as its enemy. Through the decade humanities search and tried new technologies to perfected and create
the indestructible wall.
Bricklaying work generally begins with the corners of the structure-to-be. These corners are built up
on an appropriate foundation to a height of several bricks, using a gauge-rod to determine the exact height
at which each course is to be laid. The remainder of the course is laid using a line strung between the
corners to maintain the correct height for the newly laid bricks. After the bricks have been laid but before
the mortar has set, the mortar bed is tidied and finished, a process known as pointing.
Ordinarily, parts of bricks — within a course, are arranged such that perpends do not vertically align
in any two successive courses. If this rule is observed, then the weight acting on any brick is distributed
across an area that widens with each downwardly successive course. There is a large variety of
arrangements for the cutting and orienting of bricks guaranteeing that perpends never directly align from
one course to the next. Any such arrangement is called a Bond.
There are a lot of methods on construct a wall, let alone a building. Brickwork is large field of
technology. Types of bricks and brick layering is stated. Also its functions included.
Brickwork is masonry produced by a bricklayer, using bricks and mortar. A brick is a small block of
burned clay of such size that it can be conveniently held in one hand and is slightly longer than twice its
width. Typically, rows of bricks are laid one on top of another to build up a structure such as a wall. The
standard size of a common brick are 215mm x 102.5mm x 65mm. In other cases, brickwork may be used in
a more localised way, to finish parts of buildings such as corners of walls, or door or window openings.
Brickwork is often built as a load-bearing structure. A modern load bearing brick wall often
comprises two or more separate walls tied together with wall ties. In some cases, such brickwork may have
little or no structural significance, and its primary function may even be purely decorative.
ENGINEERING BRICKS
Engineering Bricks Engineering bricks are called so due to their overall strength and water
absorption. The Class A brick has strength of 125N/mm² and water absorption of less than 4.5%. Class B
engineering bricks have a strength greater than 75N/mm² and water absorption of less than 7%.
Traditionally used in civil engineering, these bricks are also useful for damp courses and structural design.
FANCING BRICK
These bricks are designed to have a neat, even appearance. They also tend to be made from
materials high quality clay with which are interesting to look at, there is no need for plastering since they will
comprise the literal face of a building and will be the first thing people encounter when approaching. It is
designed to be seen on outside wall. While two sides of the bricks have been specially coated with
colour /decorate with pattern before the brick is fired.
Facing bricks can come in classic red, it's also possible to find cream, yellow, and other colors.
Some bricks may have inclusions which add visual texture, and facing bricks can also be stamped with
motifs or designs which are designed to make them more attractive. Facing bricks can be extruded or
molded, and in some cases may be made by hand, although handmade brick can be quite expensive
SPECIAL BRICK
They are made from fine clay with a high quality that is proposed for high durability. Finished bricks
are dense, to resist damage by exposure to weather (in which they are most used). They are usually use
for decorative purposes such at the head of a brick pier or at the feet of a gargoyle. Also, at times it is used
at the corner of an arch and specially design keystone. It comes in different unique shapes and sizes for
various purposes.
BONDING
ENGLISH BOND
This bond has alternating courses of stretchers and headers. The bricks in one course or layer
show their header faces, and alternately the other layer show their stretcher. Queen’s closers appear as the
second brick, and the penultimate brick in header courses .One of the strongest bond amongst other
bonds. The wall is 1 brick thick (89nos. of bricks/m2)
FLEMISH BOND
This is one of the most attractive bonds and was particularly popular in Georgian buildings. Flemish
bond, a course which alternates headers and stretchers is laid. Then, a course is laid on top, with the
headers in the previous course being centered under the stretchers in the new course. The course laid over
this one is oriented like the first course, and so on, creating a complex alternating pattern with the long and
short sides of the brick. The wall will be 79 nos. of bricks/m2In
STRECHER BOND
In the bricklaying field, the term stretcher bond is a reference to the format and standard to which
certain types of brick walls are built in order to be stable. Stretcher bond is the term given to the repeating
pattern the bricks are laid in. This pattern includes vertical supports tied in to the foundation of the structure
the wall is being built on. Bricks are laid with every brick showing a stretcher on each sides of wall – header
is used at angles, jambs of openings
This type of brick format is used mostly in interior settings because it is only applicable in thin-walled
settings. As a matter of fact, the stretcher bond wall is only usable in the thinnest of brick wall settings. This
is because it is only as thick as one half of a brick .A wall of 102.5mm thick or ½ brick (single brick wall)
LOAD BEARING WALL
A load bearing wall gives a building structural integrity means it supports the weight of the structure
above. It carries and distributes weight from the roof and top floors down to the foundation. Damage to a
load bearing wall can cause floors to sag, finishes to crack and the entire structure to collapse. A load-
bearing wall it. Exterior walls of a house normally bear the load, but sometimes an interior wall will also be
load-bearing to support extra weight above, such as an attic furnace or air conditioner.
Any opening in a load-bearing wall, such as a door or window, requires extra support that will shift
the load or downward pressure in the open space to extra vertical supports on both sides of the opening.
Any change in a load-bearing wall, such as adding a window or putting more weight on a roof, requires
extra support
Know that the outside walls of your home are always considered to be load bearing because these
walls support the roof. Additional support has to be given to these walls when any modifications are
performed. Load bearing wall has a support beam or there is a wall below, it's probable that it is a.
Characteristics
o It’s sometimes difficult to identify load-bearing walls, since they’re mostly concealed behind drywall. If
your home has a basement, examine the basement ceiling to find a beam or wall that follows the same
lines as a wall above it. In such cases, the upstairs wall is probably a load-bearing wall. Walls that support
ceiling joists and rafters in an attic are usually load-bearing as well. A load-bearing wall often has floor and
ceiling framing running perpendicular to it. Your home’s original blueprints can help you identify load-
bearing walls, but don’t rely solely on original blueprints if your home has been remodeled previously.
Modifications
o Consult with an architect or structural engineer before altering load-bearing walls. The walls generally
are configured to transfer equal amounts of weight to the ground through wall studs. Cutting an opening
into a load-bearing wall disturbs how the weight is distributed. An architect or structural engineer will
determine the size of the beams needed to shift the weight above an opening to each side of it to prevent
the wall from collapsing. You will probably need that type of information to get a building permit, which is
usually required to make structural changes to a home.
Wall Removal
o You may want to remove a load-bearing wall to free up floor space in your home. In such cases, the
wall must be replaced with a beam strong enough to carry the same weight as the wall. The beam may be
installed below the ceiling or inside of it so that the beam isn’t visible. Temporary support columns must be
installed to prevent the ceiling from collapsing during construction.
Materials
o The grade and type of wood or other materials used to build a load-bearing wall affect how the wall is
constructed. For example, the span capacity of the lumber used to build a home’s upper level floor joists
indicates where load-bearing walls need to be located. The span capacity is the distance that floor joists
can safely run without added support beneath them. Lumber suppliers usually have floor joist tables
available to help determine span capacity for various types of wood.
NON LOAD BEARING WALL
Building a load-bearing wall during new construction takes some engineering knowledge. Installing
a non-load-bearing wall into an existing home just requires that it be put in straight and level. Still, it's
important to follow standard procedures regarding the placement of studs and other issues so it doesn't
look cockeyed or start falling down in a year. This plan assumes you're constructing a floor-to-ceiling wall
that attaches to an adjacent wall on one side, stands alone on the other side, and doesn't need a doorway
cut into it
Instructions
1. Snap a line on the ceiling where you want your wall to go. With your stud finder, locate and mark
each ceiling joist along the span. Use your miter saw to cut a 2x4 to the length of the new wall and
screw it to the ceiling alongside the snapped line, sinking two screws at each joist. This is your
ceiling plate.
2. Hang a plumb line from each end of the ceiling plate, on one side of it, to the floor, and mark the
two points on the floor. Connect the marks with your snap line.
3. Cut two more 2x4s of the same length as the ceiling plate. One will be a top plate to screw against
the ceiling plate, and the other will be a floor plate.
4. On each of the two new boards, measure 1 1/2 inches out from the side that will touch the existing
wall, and mark a line there with your tri-square for your corner. Measure 16 inches over from that
line and mark another line for the start of the next stud. Then mark another line 1 1/2 inches over
from that one, to account for the thickness of the stud. Continue measuring across each of the
boards, marking lines for studs every 16 inches. At the open end of the wall, mark for three studs in
a row, pressed together.
5. Measure from the bottom of the ceiling plate to the floor, then subtract three inches from that
number. That's the length you need for your studs. Cut enough 2x4s at that length to stand
between each of the paired marks you've made on the floor plate and top plate.
6. Lay the top plate and floor plate on their edges, their marked sides facing each other, the boards far
enough apart to fit the studs between them. Attach each stud to the floor and top plates by sinking
two screws through the far side of the plate and into the ends of the stud. Frame out the whole wall.
7. Stand the wall up, with the floor plate along your floor line and the top plate butting up under the
ceiling plate and even with it on all sides. Screw the top plate into the ceiling plate, sinking several
screws upward on the flat spans of the top plate between each pair of studs.
8. Put a level on the outer edge of the new wall and move the bottom part of it out or back if necessary
to get it level. Then screw the bottom plate onto the floor, sinking screws on the flat spans between
the studs. Your wall is now ready for electricity installation if necessary, and drywalling.
FUNCTIONAL REQUIREMENTS FOR BRICKWALLS
i. Strength
Resist compressive & tensile stress.
Stability
Resist overturning by lateral force & buckling caused by excessive slenderness.
May be affected by foundation movement, eccentric loads, lateral forces (wind) and expansion due
to temperature and moisture changes.
ii. Weather & Ground Moisture Resistance
Primary concern is penetration of moisture, vapour & dampness.
iii. Durability & Maintenance Free
Cost of maintenance of wall over a number of years depend on its durability.
The common material used as walling for permanent building is the well-burned brick which durable,
fire resistance and had good appearance of the material.
iv. Fire Safety
Fires in buildings – the outbreak of fire or spread of fire
Fire safety regulations are concerned to assure a reasonable standard of safety in case of fire eg:
provide adequate means of escape, limit internal fire spread, limit external fire spread.
v. Thermal/ Heat Resistance
To maintain satisfactory internl condition of room/space.
Factors affecting thermal properties of wall are: density,type of base material, type of construction,
openings & heat transmission properties.
vi. Sound Insulation
Noise generated in a room may be reflected from the walls and ceilings and build up to an
uncomfortable intensity inside the room.
To prevent the build-up of reflected sound some absorbent material should be applied to walls and
ceilings, such as acoustic tiles or curtains, to absorb the energy of the sound waves.
Characteristics of wall that can provide sound insulation are thickness of wall, continuity of room
design & material used.
Apart from the type of brick, and the type of bonding is concern. There is also the technology of the
type of the wall need to be considered. In the concern for the environment and weather, the type of wall is
also used. In this case the cavity wall was used to solve the problem created by the three main elements,
which is water, wind and sun. Water would create such problem as mold and brick expansion which is
known to be absorbent and causing cracks. The wind causes erosion to the bricks. Lastly, the heat from the
sun would over evaporate the moisture from the bricks and consequently alternating from expansion to
shrinkage would eventually cause it to crack. Thus, the using of cavity wall expand the life span of a wall.
CAVITY WALL
Cavity walls consist of two 'skins' separated 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. A cavity wall with masonry as both inner and
outer skins is more commonly referred to as a double wythe masonry wall
Function
An added benefit of cavity wall construction is that it provides the ability to more adequately insulate
the building. A continuous layer of rigid insulation is easily fitted between the cavity and the inner skin of the
wall. The insulation does not fill the cavity but rather slip in behind it. The cavity itself also helps in
insulating the building by acting as a thermal break between the two skins of the wall.
The reason cavity insulation keeps heat in is that the polymer and air in the cavity are good
insulators. This is because the distance between the particles in the air is greater than in a solid. Other
benefits of cavity walls are their resistance to moisture from the outer side to the inner wall and the increase
of sound proofing.
MORTAR
Mortar is a workable paste used to bind construction blocks together and fill the gaps between
them. The blocks may be stone, brick, cinder blocks, etc. Mortar becomes hard when it sets, resulting in a
rigid aggregate structure. Modern mortars are typically made from a mixture of sand, a binder such as
cement or lime, and water. Mortar can also be used to fix, or point, masonry when the original mortar has
washed away
Mortar nomenclature has developed over many years to its current form. Designations for mortar
are found in ASTM C 270, Standard Specification for Mortar for Unit Masonry. In the United States, the
three common types of mortar specified for new construction today are N, S, and M. These arbitrary
designations were assigned by taking every other letter from the term “mason work.” Astute observers will
notice that an “O” and a “K” also appear in that term. While these are recognized mortar types, they are
typically used for non-load bearing walls and for tuckpointing or other repair work.
Mortars are differentiated primarily by their strength: M is the highest strength, S is next, and N is a
moderate strength mortar. (O and K are lower strengths yet, which is important in repair work so as not to
create a mortar that is stronger than the wall/units where it is being placed.)
If you think the strongest mortar is the best solution, think again. True, strong mortars do generally
have increased durability and greater structural capacity. But, since much masonry is constructed as
reinforced masonry today—there are steel bars added to the cavity then grouted solid to create a
“concrete” wall—the reinforcement and grout become the more dominant structural elements. The mortar
itself is less important for its load carrying capacity than for its other aspects, such as facilitating placement
of units.
Rule of Thumb: Use a Type N mortar for all masonry work unless there is a compelling reason to
choose another mortar. C 270 provides recommendations for mortars choices in a concise tabular format
as shown here. Note that alternative mortar types are also suggested, whether for availability
considerations or for minimizing the number of different mortar types on the job site. Consult the appendix
of C 270 for tuckpointing mortar guidance.
Location Building SegmentRecommended
Mortar
Alternati
ve Mortar
Exterior, above
grade
Load-bearing walls
Non-load bearing walls
Parapet walls
N
O
N
Sor M
N or S
S
Exterior,
at or below grade
Foundation walls,
retaining walls, manholes,
sewers, pavements, walks and
pations
S M or N
Interior Load-bearing walls N S or M
Non-load bearing walls O N
From ASTM C 270
Portland cement mortar (is very often known simply as cement mortar) and is created by mixing
Ordinary Portland cement (OPC), hydrated lime, and clean river sand) with water.
Function
Bind construction blocks together and fill the gaps between them.
To arrange the bricks in such a way as to prevent long lines of cleavage
Basic requirements
Will harden to such extent that it can carry the weight carried by bricks without crushing
Must not deteriorate due to weather effect
LIME MORTAR
Slaked lime is used to make lime mortar. The mortar is made by mixing sand with slaked lime at the
proportion of 1 part lime to 5 parts sand. There are two types of lime used in lime mortars, one that sets
and hardens by the reaction with the air (non-hydraulic) and one which sets by reaction to the water
(hydraulic).
Non-hydraulic lime is made from pure calcium carbonate, or chalk or limestone.
This is burned in a kiln to create calcium oxide or quicklime. When this is slaked with water it takes
on another form as calcium hydroxide. Calcium hydroxide reacts with the air to set. This is what sets the
brickwork together and creates the strength.
Hydraulic Limes. Calcium carbonates naturally occur but can include some impurities. It is these
impurities which when burned in a kiln create the calcium silicates or aluminates that react with water to
set. Enough water is added to the mixture to create calcium hydroxide powder form. The hydraulic lime is
then graded depending on their overall set strength.
JOINTING
In masonry, mortar joints are
the spaces between bricks, concrete
blocks, or glass blocks, that are filled
with mortar or grout. Mortar joints in
brickwork take up a considerable large
amount of a wall’s surface area and
have a significant influence on the
wall’s overall appearance. Some joint
profiles accentuate their individual
designs, while others merge the bricks
and mortar to form a flush,
homogeneous surface. Mortar joints
vary not only by their appearance, but
also by their water-resistance properties.
The finish of mortar joints between bricks to provide a neat joint in brickwork that is finished fairface.
Fairface -finished face of brickworks that will not/need not to be covered by plaster, rendering etc. Joint is
made when mortar is hardened sufficiently Joints are expensive - laborious
Brick masons use cementitious mortar to create strong, stable joints between rows of clay bricks.
While the look of these joints may seem like an afterthought for those focused on the beauty of brick,
mortar joints actually make up as much as 17 percent of a brick structure according to the Brick
Development Association. To maximize the appearance and function of your brick surfaces, take the time
to choose from different types of brick joints based on the needs of each project
TYPES OF JOINTS
Concave brick joints represent one of the most popular mortar profiles used in modern brick
construction. Bricklayers use a curved tool, known as a bucket handle, to compact the mortar between
each brick. The compacted mortar takes the rounded shape of this tool and curves in away from the face of
the wall.
Flush mortar joints allow brick workers to create a smooth wall surface. They use a trowel
to wipe away excess mortar so that the mortar sits flush with the face of the brick. This type of installation
does little to compact the mortar, leaving it vulnerable to moisture penetration over time. Because they lack
natural moisture-resistance, these joints are often used on walls that will be covered with paint or plaster,
rather than on walls where the brick will be left exposed.
V-joint mortar profiles feature a sharply angled design that can be created using a V-shaped
tool or simple wooden block. These tools help to effectively compact the mortar within the joint, which offers
some protection against moisture damage. A V-shaped joint is often used to conceal irregularities between
different courses of brick and give it a more structured appearance.
Squeezed joints serve as one of the simplest mortar joints that bricklayers can create. To utilize a
squeezed joint, workers apply mortar to each brick without wiping off excess mortar. This allows some
mortar to squeeze out from between the bricks and cascade down the face of the wall, giving the structure
a rustic, classical design.
Raked joints consist of rectangular profiles recessed into the mortar between each brick. Bricklayers
achieve this design using a raking tools, which removes a small amount of wet mortar from each joint. The
squared edges of a raked joint may allow water to collect around the mortar, which could lead to
maintenance problems over time.
Struck joints feature an angled top edge and a squared bottom edge. They are achieved using a
trowel that's pointed down to remove excess mortar from the bottom half of the joint. This squared edge
poses some of the same maintenance issues as with raked joints..
Weathered joints represent the opposite of a struck joint. Workers create these joints by angling the
trowel up to remove excess mortar from the top half of the joint. This design helps to emphasize the clean,
straight lines of the brick and poses none of the moisture issues of raked or struck joints.
Beaded brick joints give a structure a formal, old-fashioned look. Bricklayers create this look using a
special mold that creates a convex joint with a second thin curve along the center. This thinner curve
creates a unique shadow pattern. The inverse of this profile is a grapevine joint, which is created using a
grapevine tool. Grapevine joints are often associated with Colonial architecture according to the
International Association of Certified Home Inspectors
POINTING
Mortar joints in brickwork take up a considerable large amount of a wall’s surface area and have a
significant influence on the wall’s overall appearance. Some joint profiles accentuate their individual
designs, while others merge the bricks and mortar to form a flush, homogeneous surface. Mortar joints vary
not only by their appearance, but also by their water-resistance properties. Operation of filling mortar joints
with a mortar selected for colour & texture. Special mix of lime, cement & sand or stone dust chosen to
produce particular colour & texture. Also for protection for mortar to enhance weather resistance.
The type of joint between bricks affects not only a wall's appearance, but also the mortar's
resistance to weather and, in turn, the longevity of the entire wall. Masons employ a variety of trowels, or
pointers, to retool, or "point," mortar joints for repair purposes or following initial installation. The types of
brick pointing used range from minimal and fast swipes across the joint's surface to detailed, sloping or
concave angles within the joint.
TYPE OF POINTING
A flush mortar joint is neither recessed nor protruding from the wall--the mortar is flat relative to the
surrounding surface of the bricks. Flush pointing is typically performed during the installation of the brick
wall; after laying a course of brick, the excess mortar is cut, or swiped, away from the brick's surface,
leaving a flat mortar joint.
The concave joint, also called "bucket handle," is a rounded mortar joint. This type of pointing
forces the mortar to curve toward the wall's interior in a half circle shape. Builders use special pointing
trowels and, sometimes, pieces of pipe to create this joint. Because of its sloping curve, a concave joint
carries water away from the wall, improving the mortar's resistance to weather.
A weatherstruck joint increases resistance to weather by angling the entire mortar joint outward. A
trowel is used to shape the mortar into a slope angle away from the interior of the wall, downward from top
to bottom. This method of pointing requires a steady hand to create a uniform, smooth mortar joint.
A raked joint, also called recessed, is flat like the flush joint. A raked joint's unique characteristic is
that its surface is recessed in relation to the surrounding bricks. Although the raked joint lends the wall an
attractive sense of depth, it allows moisture to accumulate around a mortar joint. Raked joints are
considered the least weather-tight of joints.
Tuck pointing is a special masonry technique that uses colour in an attempt to create a seamless
connection between brick and mortar. To create a tuck pointed joint, masons recess mortar as courses of
brick are laid, returning later to fill the joints with mortar of the same colour as the brick. Tuck pointed joints
are typically fashioned in a flush style.
The video is about brick installation and drainage wall. These facts and function is either stated
above or below. It is shown that the method and technologies use in the video are by using common mortar
and stretcher bond for the cavity wall. Here, it is shown on how the brick is layered, on how mortar is
prepared. Installation of brick on foundation wall too is shown. On how the drainage cavity was used and
how further apart is the cavity will the walls. Installation of flashing at wall interface is also shown as to
emphasize the need of the flashing to prevent moisture in the wall. Then, they install felt building paper as
to support the function of the flashing to the wall.
Both these ‘papers’ is nail in to the inner leaves of the wall. While the brick is layered weep holes is
installed for the moisture in the cavity to weep out and evaporate, the concept is to give a way out for
moisture in the cavity. After several layers of bricks they install wall ties to keep the wall closed and
correctly placed. When they reach the window level, they gave the window flashing at least two inches tall
damp to prevent water from entering the cavity and let it trickle down the sill. The same concept was done
to the roof and door with slightly different technique.
I learn of each meaning of the term and the function of it. Furthermore i have got to known on how it
is installed respectively. These is what I have learn from video. I have benefited a lot from this video as to
have learn about precious knowledge that would be gold in my field of studies.
FLASHING
Flashing refers to thin continuous pieces of sheet metal or other impervious material installed to
prevent the passage of water into a structure from an angle or joint. Flashing generally operates on the
principle that, for water to penetrate a joint, it must work itself upward against the force of gravity or in the
case of wind-driven rain, it would have to follow a tortuous path during which the driving force will be
dissipated. Exterior building materials can be configured with a non-continuous profile to defeat water
surface tension.
Flashing may be exposed or concealed. Exposed flashing is usually of a sheet metal, such as
aluminium, copper, painted galvanized steel, stainless steel, zinc alloy, terne metal, lead or lead-coated
copper. Metal flashing should be provided with expansion joints on long runs to prevent deformation of the
metal sheets. The selected metal should not stain or be stained by adjacent materials or react chemically
with them.
Flashing concealed within a construction assembly may be of sheet metal or a water proofing
membrane such as bituminous fabric or plastic sheet material, depending on the climate and structural
requirements. Aluminium and lead react chemically with cement mortar. Some flashing materials can
deteriorate with exposure to sunlight.
One of the biggest indicators of how long a home will last is its ability to shed water. This is because
moisture that penetrates into the building will quickly rot the wood building structure and/or lead to the
growth of mold and fungus. Preventing this water penetration is done with the correct installation of
flashing. Through-wall flashing needs to be installed prior to application of the brick or siding. Its job is to
move water that has accumulated behind the brick or siding to the exterior of the building
1. Measure the length of the bottom of the wall with a measuring tape. Transfer this measurement to
the through-wall flashing and cut to length using tin snips.
2. Hold the through-wall flashing so its bottom runs along the foundation and its side is flush with the
wall. The bottom of the flashing needs to extend past the foundation by about 1/2 inch and bend
downwards.
3. Secure the flashing to the wall with one nail at every wall framing member. The nails need to be as
high up the wall as possible. Never install a nail near the bottom. This provides a path for the
moisture to enter the wall.
4. Install The exterior wall membrane over the entire wall by stapling it to the wood sheathing. The
membrane should overlap the flashing and extend to the inside of its corner.
5. Install the bricks or siding on the wall system. If the wall is brick, a weeping hole should be provided
every five feet along the bottom course. This is done by removing the mortar from the vertical joint
at the desired locations.
WEEP HOLES
Weep holes or "weeper holes" are small openings left in the outer wall of masonry construction as
an outlet for water inside a building to move outside the wall and evaporate.Weep holes are located near
the base of masonry structures, particularly brick buildings. Raising the grade above weepholes may allow
moisture, snakes, insects, and small animals to enter the building. Modern weep holes employ screens,
constructed of flexible nylon or plastics. Typically, drain tiles have weep holes, which allow water to enter
the tile.
They serve two important purposes. Ventilation of the internal wall cavity - Without ventilation,
mildew, dry rot and damp reduce the life of the internal wall studs and other building materials within the
cavity. Inadequate ventilation is the main cause of "Leaky House Syndrome".Drainage - Water that enters
the cavity due to capillary action, condensation, damage, or accidental flooding needs to escape
somewhere. In tropical and sub-tropical areas of Australia it is not unusual to see water flowing from the
weep holes on the prevailing side of well constructed houses after a 'gully raker' or monsoonal storm.
a highly porous absorbent paper used in the manufacture of some building and roofing papers
Weep holes may seem a small part of masonry wall construction, but they are critical to the
durability and performance of cavity walls. Weep holes should be installed in the masonry head joints
above all flashing courses. This includes the base of the wall, above all window and door lintels, and above
shelf angles. Anywhere the cavity is interrupted, you must install flashing and weeps. There are several
ways to form weep holes.
Each type has a different appearance as well as advantages and disadvantages. Open head joints
are most common type is the open head joint. Open head joints are easy to form. Mortar is left out of the
joint, leaving an open channel that is 3/8 inch wide by course height by veneer depth. Plastic tubes is
hollow plastic tubes also are used to form weep holes. The most common ones are 1/4 or 3/8 inch in
diameter by 3 1/2 to 4 inches long. Manufacturers recommend installing them at an angle in the mortar of
the head joints, spaced 16 inches apart.
Cotton wicks are used to form another type of weep system. A 1/4 to 3/8 inch diameter rope is
installed in joints at 16 inches on center. The rope should be 10 to 12 inches long and extend through the
veneer face and up into the cavity wall above the height of any possible mortar droppings. Moisture in the
cavity is absorbed by the cotton material and wicked to the outside face of the wall where it evaporates. Oil
rods or ropes as another alternative for cavity wall drainage are oiled rods or ropes mortared into bed joints
16 inches apart and then removed when the mortar has set. The rods function much the same as plastic
tube weep holes.
For a cavity wall to function properly, water that collects on flashing must be able to drain through
weep holes to the exterior of the building. If weep holes do not function properly, water collecting in the
cavity can infiltrate to the building's interior. For proper drainage cavity walls must be detailed correctly and
constructed to keep the cavity clear of mortar droppings and prevent weep hole blockage. The most
common types of weep holes are open head joints, louvered vents, rope wicks, tubes, cellular vents, or a
combination of these.
TYPES OF WEEP HOLES
Open head joints
Unmortared head joints
Spaced at regular intervals at the base of the cavity, are highly effective and are the easiest type of
weep hole to construct. Louvered vents: Louvered aluminum or plastic vents sometimes are used in
conjunction with open head joints to keep insects out of the cavity. Rope wicks: Cotton sash cord also is
commonly used for weeps. The cotton fibers have a wicking effect that draws moisture from the cavity to
the exterior of the building. Tubes: One-quarter-inch-diameter plastic or metal tubing, cut slightly longer that
the thickness of the wythe, is mortared in place as the course immediately above the flashing is laid.
Cellular vents: Plastic cellular vents consist of many small, adjacent passageways bonded together in one
unit. The cross section is similar to that of a honeycomb. Prevent mortar build up is the best way to assure
proper drainage of water is to maintain a cavity that is free of mortar droppings. This requires good
workmanship and construction.
FELT BUILDING PAPER
Tar paper also known as felt building paper is a heavy-duty paper used in construction. Tar paper
is made by impregnating paper with tar, producing a waterproof material useful for roof construction. It can
be distinguished from Roofing felt:Asphalt-saturated felt. Roofing felt has been in use for over a hundred
years. Originally felt was made from recycled rag but today felts are made of recycled paper products
(typically cardboard) and sawdust.
The most common felt product is the so-called #15 felt.Wall ties are used in cavity walls to connect
the outer and inner walls, or to connect a new masonry wall to an existing one. Designs vary according to
whether a tie is for use with masonry or timber. Some common examples are shown below. Small metal
strip or steel wire used to bind courses of masonry to wood frame in veneer construction.
Installing felt paper is an important part of installing new shingles on a roof, as it helps to protect the
roof from moisture and may be required by state and local law as well. Felt paper should be applied directly
to the roof itself, meaning that it is intended for installation on new roofs or on roofs where all shingles have
been stripped off before new asphalt shingles are installed. It isn't difficult to install felt paper, especially if
you have someone to help you with it. After the felt paper has been installed, your shingles can be installed
directly over the paper
Factors affecting nature of the brickwork ;
Force of Nature
Most of us live in climates influenced by rain and wind. During a storm, a thin film of water clings to
windward surfaces. Porous materials, like unfinished shingles, stained wood clapboards, and masonry
veneers soak up water. Non-porous materials like freshly painted wood, aluminum and vinyl do not. But the
film of water sticks to all siding products. As the wind’s speed and direction shifts, water moves up, down
and sideways under the influence of air pressure. It moves from areas of high pressure to areas of low
pressure. The area directly behind a wind-blown wall surface is at a lower pressure than its exterior face.
This pressure difference works to suck the water inward through any hole it finds. Stripped problem walls
immediately after heavy rain to monitor rain intrusion and establish moisture profiles. It is perfectly clear
that butt-joints, seams, holes, and siding overlaps are siphon points driven by air pressure, gravity and
capillary suction. If there is no building paper, water will get wicked up into the wood sheathing where is
often causes structural problems.
Many carpenters make the mistake of thinking that siding – wood, brick, vinyl, stucco – is an
impenetrable barrier against the elements. The truth is, whether water is propelled by wind, capillary
attraction, gravity, or some combination of these forces, sooner or later it finds its way behind, around or
through the siding. Local code may not require you to use felt or housewraps, but unless you live in an
extremely arid climate — you need to use it. Typically, building paper is installed as soon as the sheathing
is installed. But to be effective, it must be integrated with the flashing that follows in later stages of the job.
This means, for example, having to slit the housewrap above windows to tuck under the upper leg of a
metal cap flashing, then taping the wrap to the flashing. And the wrap itself must be properly layered,
overlapped and taped where necessary to provide a clear drainage path (see Watertight Walls article.)
Barrier Design
There are basically 3 types of weather-barrier systems: the sealed-face method; the vented rain-
screen approach; and the redundant-barrier system. The sealed-face method is straight out – non-effective.
The vented rain-screen approach is clearly the Mother of all weather-barrier systems. However, the
redundant-barrier approach works well and is the most cost effective option.
The vented rain-screen is a system where lengths of strapping are fastened to housewrap-protected
wall sheathing. Siding is attached to the strapping leaving an air space between the back of the siding and
the face of the sheathing. This design does 2 very important things: The air pressure between the air on the
outside of the siding and the air space created behind the siding is similar (if the siding is leaky to air).
Therefore, rainwater is not sucked through the penetrations in the siding. No driving force! The second
strength of this system is that the air space behind the siding promotes rapid drying if any water does get
past the siding.
Constructing a rain screen is somewhat costly and labor intensive. Installation is unconventional, so
it requires rethinking of some details. Window and door trim must be padded out. Flashing should be
extended back to the sheathing beyond the air space and under the housewrap. Door hinges may need to
be extended, so doors can be fully opened. Roof overhangs at gable ends must be extended to cover
thicker wall sections. The bottom of the air space must be covered with screening to prevent critters from
entering the vent chamber. These and other accommodations are certainly doable, but involve more labor
and materials than typical construction. In my opinion, rain screens are required fare for wet, wind-blown
areas like the Pacific Northwest, exposed coastal environments and hilltop exposures. But, this approach is
not required or cost-effective for most climates and construction budgets.
The redundant-barrier works well for the vast majority of homes built today. And this system has the
advantage of being familiar to builders. Basically, putting tar paper or approved housewrap on the exterior
walls before siding is installed is the first step to build an effective redundant-barrier system. Proper
installation is required to make this system work. You must design a drainage plane that keeps water out!
When water penetrates the siding, it must have a clear path to follow downward. Water must remain
outside of the protective wrap. Be sure that tops of windows, doors and penetrations are flashed properly
(see Making Walls Watertight). All water must be directed outward. Also, we must choose materials that are
capable of providing the protection we expect and need. The barrier should be resistant to liquid water and
air infiltration, while being permeable to water vapor.
CONCLUSION
It can be concluded that brickwork is a very interesting field to get involve with. Is is very important
for a quantity surveyor to know its brickwork very carefully and detail because it can affect the cost of the
subject when using certain technologies in doing even a simple construction project. Brick is a virtually
maintenance free material that resist the elements, as well as moisture compare to other material, fire or
heat, and much general wear and tear. It is also fairly soundproof, and does not lose its colouring with age.
Before the mortar is mixed, lay the first set of bricks or try a full dry run to ensure that the design
works on the selected earth slot. On any brickwork, the vertical joints are staggered and do not line up
making the wall more stable. It is prominent to allow space for the mortar in between each brick (about
10mm). Use the spirit level to practice adjusting the vertical and horizontal planes.
Highly important to the creation of a solid and lasting wall is the laying of good foundations. The
foundations must be strong enough and deep enough to bear the weight of the brick wall. This much of
knowledge should be the basic of a construction involve personal.
Good quality bricks have a major advantage over stone as they are reliable, weather resistant and
can tolerate acids, pollution and fire. Bricks can be made to any specification in colour, size and shape
which makes bricks easier to build with than stone. Brickwork is also much cheaper than cut stone work.
However there are some bricks which are more porous and therefore more susceptible to dampness when
exposed to water. For best results in any construction work, the correct brick must be chosen in
accordance with the job specifications. You are as good as your weakest link. Thank you.
The shell of a house serves as the first line of defense between the occupants and the outdoor
environment. Walls function as a weather barrier, nail base for finish materials and an energy conserving
boundary. A sensible wall system is durable. And this requires all components in a wall assembly to be
compatible for the long haul. Siding, siding finishes, housewraps, insulation and wall frames must work
together while achieving distinctive goals. So it is in this light that we should view a primary, but often
overlooked, component in residential wall systems: weather-resisting wall wraps.
Wood, brick, masonry, vinyl, and other sidings do not function as barriers to driving rain. Siding is porous.
There are a multitude of joints, laps, and connections making it discontinuous. Water and air are driven
through these leakage points by wind, gravity and capillary forces. Also, we generally use water-sensitive
materials for siding and structural elements. Leaking water rots wood, grows mold, corrodes steel and
lowers insulating R-values. Another concern is that leaking air strips heat from homes and dollars from
energy budgets. So air-tight construction is desirable.
ADVANTAGE OF USING CAVITY WALL
Wall. Wall insulation systems help to keep homes more energy-efficient and comfortable. According to
Energy Saving Trust, "If your home was built from 1920 onwards, the chances are that its external walls are
made of two layers with a small gap or 'cavity' between them." This empty cavity is what led to the need for
insulating material. There are many advantages, as well as disadvantages, that accompany wall insulation
Advantage—Energy Efficiency
Unlike conductors, insulators are poor transmitters of heat. This characteristic explains why wall
insulators are energy-efficient. They slow down the rate of heat transfer and restrain heat within the
house as long as possible; hence, there is less of a need to use energy to achieve and maintain a
comfortable room temperature, especially during winter. Since wall insulators prevent heat loss,
they save on energy costs. Wall insulators also prevent the penetration of too much heat from the
external environment, which is especially useful during summer.
Advantage—Friendly to the Environment
Wall insulation is normally made up of air barriers, vapor retarders and thermal bridges--all of which
contribute to preventing heat from escaping through the walls of homes. By reducing heat loss, as
well as cool air that is lost during the summer, wall insulation reduces emissions to the environment
by reducing the use of heaters and air conditioners, which helps to reduce electricity consumption.
As the majority of power plants that produce electricity also produce carbon dioxide, lowering
energy consumption can reduce pollution. According to Green Street, "Wall insulation can reduce
heat loss by up to 40% through cavity walls and up to 60% through solid walls. It is therefore one of
the most important energy-saving measures to consider."
Advantage—Noise Reduction
Insulating walls also reduce noise. Insulators between walls act as absorbers and barriers to
decrease noise being carried to adjoining rooms.
Disadvantage—Rain Penetration
According to the Building Research Establishment, cavity wall insulation does not totally prevent
rainwater from penetrating the “outer leaf of masonry.” The rainwater creates moisture which then
causes “dampness on internal finishes.”
Disadvantage—Health Risks
Some materials used for wall insulation pose health risks. Asbestos, for example, has been known
to cause mesothelioma, a form of lung cancer, and gastrointestinal tract cancers. Fiberglass, a
commonly used material for insulation, can cause skin allergies due to the chemicals used to bind
the fibers together.
In addition, styrene, a foam insulator, can cause health risks—ranging from eye and respiratory irritation to
possible effects on the liver and the reproductive system.
REFERENCE
http://www.interstatebrick.com/faqs/Whatarethecorrectproceduresforrepointingbrickwork.html
http://en.wikipedia.org/wiki/Weep_hole
http://www.merriam-webster.com/dictionary/felt%20paper
http://en.wikipedia.org/wiki/Flashing_(weatherproofing)
http://www.diynetwork.com/diy/windows_walls_and_doors/article/0,1000642,DIY6047522_04,00.html
http://bct.eco.umass.edu/publications/by-title/housewraps-felt-paper-and-weather-penetration-barriers/
http://www.wisegeek.com/what-is-stretcher-bond.htm
http://www.builderregister.com/brickwork.php
http://www.brickdirectory.co.uk/html/brick_history.html
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