After the foundations have been completed the
walls are set out and construction commences.
wall structures
Walls
Walls can be classified in a number of ways:Solid
Cavity
Internal
External
Load bearing or
Non load bearing
Load bearing – supporting roofs, floors etc.
Non load bearing – Dividing spaces
Main functions of walls
1.
2.
3.
4.
5.
6.
7.
8.
Strength
Stability
Weather exclusion
Thermal Insulation
Sound Insulation
Durability
Fire resistance
Appearance
Part of a cavity wall with the internal
skin removed to expose the
Insulation
Bonding of Brickwork / Blockwork
Bonding of brickwork is the
arrangement of brickwork in a wall,
column or pier which will give maximum
overlap and no continuous vertical
joints. The purpose of bonding is to:-
1.
2.
3.
LOAD
Obtain maximum strength whilst
distributing the loads carried by the
walls.
Ensure lateral stability and
resistance to side thrusts.
Create an acceptable appearance.
Possible settlement
Unbonded walls – Comparatively weak and liable to fail under load or lateral
thrust.
Bonding of Brickwork / Blockwork
• Bonded wall – load is
distributed over the whole
wall and has greater
resistance to side thrust.
Standard brick sizes
LOAD
Length + one mortar joint =225mm
Width + one mortar joint =112.5mm
Height + one mortar joint =75mm
Mortar joint thickness = 10mm
SPREAD OF LOAD
Stretcher Bond
This is the simplest and most widely used bond. It
is used for half brick walls and cavity walls. The
bricks must lap over each other in successive
courses in a fashion similar to the one shown
below.
Half lapped
Formation of a corner in
stretcher bond
½ bat to form
stopped end
Racking-back
Return corner of a cavity wall in stretcher
bond including wall ties and DPC
Cavity
Wall tie
Quoin
D.P.C.
Perpendicular
mortar joint
Horizontal
mortar joint
Wall Ties
There are a large variety of
different types of wall ties,
but they all have two basic
requirements of:(a) Tieing the outer and inner
leaf of the cavity wall
together.
(b) Prevent moisture passing
from the outer to the inner
skin of brickwork.
Most wall ties are currently
made from stainless-steel or
nylon.
Stainless-steel wire
wall tie with plastic
disc to hold sheet
insulation in place.
Spacing of wall ties
Mortar droppings must not be allowed to accumulate on wall ties because this
would form a bridge for water to pass from the outer to inner leaf.
The cavity should start
150mm below the lowest
damp proof course. In
facing brickwork every
4th vertical joint is left out
at the base of the cavity
to allow any build-up of
moisture at the base of
the cavity to escape.
Types of pointing
Curved Recessed
Struck or weathered
There are several types of pointing which
can be used with facing brick, Curved
recessed or ( pole jointed as it is commonly
called in N. Ireland) is the most popular.
Cavity walls in block
construction
A cavity wall consists of two ½
brick thick leaves with a cavity
between them. The outer leaf in
conjunction with the cavity acts
as a barrier to moisture. The
Inner leaf supports most of the load
from floors and the roof. If heavier
loads than usual have to be
supported the inner leaf can be built
one brick thick or more. There is no
need to increase the thickness of the
outer leaf.
Section through a Cavity Wall
Rain
Wall tie
Outer leaf
facing brick or
block and
render.
D.P.C.
The two leaves of the wall must be tied together with
Stainless-steel cavity wall ties.
Cavity walls in brick
construction with insulation
• This wall is similar in construction to the
first cavity wall, the only exception being
the inclusion of insulation.
• Wall ties are manufactured from
stainless steel.
60mm thick insulation
Insulation
Vertical DPC at
window and
door jambs
Plaster
Timber stud walls
Stud partitions are still
extensively used for internal
walls of domestic buildings.
100 x 50 timber studs
These are non load bearing
internal dividing walls which
are easy to construct,
lightweight, adaptable and
can be clad and filled with
various materials to give
different finishes and
properties.
Door opening
Timber stud walls
General construction consists of 100 x
50mm or 100 x 75mm sole plate and
head plate. Vertical members or studs
made from 100 x 38mm or 100 x
50mm members are nailed in between
at 400mm centres.
Section A A
100 x 50mm stud
Architrave
The spacing is to suit the plasterboard
or other cladding material.
Nogging or bridging pieces are inserted
between the studs to stiffen the
partition.
The timber frame is then covered with
Plaster Board
plasterboard on both sides and finished
with a 3 to 5mm coat of plaster.
Door
Planted door stop
100 x 50mm stud
Timber stud walls
100 x 50mm head plate
Ceiling joist
A
Plaster board
A
Door
opening
Floor joist 100 x 50mm sole plate 100 x 50mm studs at 400c/s