wall structures

1
wall structures
After the foundations have been completed the
walls are set out and construction commences.
2
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

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Main functions of walls

1. Strength
2. Stability
3. Weather exclusion
4. Thermal Insulation
5. Sound Insulation
6. Durability
7. Fire resistance
8. Appearance

Part of a cavity wall with the internal skin
removed to expose the Insulation
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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-
• Obtain maximum strength whilst distributing the
  loads carried by the walls.
• Ensure lateral stability and resistance to side
  thrusts.
• Create an acceptable appearance.

LOAD
Possible settlement
Unbonded walls Comparatively weak and liable to
fail under load or lateral thrust.
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Bonding of Brickwork / Blockwork
LOAD

• Bonded wall load is distributed over the whole
  wall and has greater resistance to side thrust.
• Standard brick sizes
• Length one mortar joint 225mm
• Width one mortar joint 112.5mm
• Height one mortar joint 75mm
• Mortar joint thickness 10mm

SPREAD OF LOAD
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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
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Formation of a corner in stretcher bond
½ bat to form stopped end
Racking-back
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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
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Wall Ties

• There are a large variety of different types of
  wall ties, but they all have two basic
  requirements of-
• Tieing the outer and inner leaf of the cavity
  wall together.
• 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.
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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.
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• 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.
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Cavity walls in block construction
Section through a Cavity Wall

• 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.

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.
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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
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Timber stud walls
Stud partitions are still extensively used for
internal walls of domestic buildings. 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.
100 x 50 timber studs
Door opening
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Timber stud walls
Section A A
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. 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 plasterboard on both sides and finished with
a 3 to 5mm coat of plaster.
100 x 50mm stud
Architrave
Door
Planted door stop
Plaster Board
100 x 50mm stud
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Timber stud walls
100 x 50mm head plate
Ceiling joist
A
A
Door opening
Plaster board
100 x 50mm studs at 400c/s
Floor joist
100 x 50mm sole plate