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Unit 204
Building solid walling, isolated and attached piers
This booklet covers learning outcomes 1.41.53.53.63.73.83.93.125.105,11
SOLID WALLS
What is a solid wall? - generally a wall having a thickness of 215mm (1 brick) or greater.
What are solid walls used for? -generally for strength.
State 3 examples where solid walls would be used.
1 Boundary / garden wall
2 Retaining wall
3 Inspection chambers or manholes
Solid walls can be formed by constructing a series of walls laid in Stretcher Bond, however unless these ‘skins’ are ‘tied’ together, problems could occur, such as separation or crushing together, so for strength reasons solid walls are generally constructed laying the bricks positioned as headers and stretchers, creating a wide variety of bonds.
Even though each bond has its own name they are all classed as being Quarter Bonds.
Remember, a half-bat placed at the end of a wall, creates Half Bond. Therefore what size bat would you need to place in a wall to create Quarter Bond?
A. Quarter bat
The name given to this brick bat is a:
A. Queen Closure
QUOINHEADER
QUEEN CLOSURE
COLLARJOINT
Bonding arrangement at a Quoin (English Bond)
The 2 most common solid wall bonds are:ENGLISH BONDFLEMISH BOND
ENGLISH BOND – consists of alternate courses of HEADERS and STRETCHERS.
It makes no difference whether you begin the walling by laying Headers or Stretchers.
Ideally used for walls requiring strength to resist vertical and lateral stresses.
On the elevation below, draw in the bonding arrangement for an English Bond wall 7 bricks in length.
Use a PENCIL and a RULER
English Bond
FLEMISH BOND – consists of alternate HEADERS and STRETCHERS, on the same course. The same arrangement is created on each course.
Not as ‘strong’ as English Bond but has a more ‘pleasing appearance.
Because bricks vary in length the rear side of an English bond wall can become very ‘bumpy’
The headers in Flemish bond are dispersed more giving a ‘smoother’ finish to the rear of the wall.
Because of this it is recommended that Flemish Bond is used in preference to English Bond for walls requiring a ‘face’ both sides and where ‘strength’ is not as important.
On the elevation below, draw in the bonding arrangement for Flemish Bond.
Use a PENCIL and a RULER
Flemish Bond
If you have bonded this wall correctly you should notice that the positions of the Stretchers and Headers are symmetrical. Because of this symmetry Flemish Bond is ideal for creating ‘patterns’. (Polychromatic and Photochromatic brickwork)
Decorative patterns can be formed by :
1 Using specially Cut / patterned bricks
2 Using contrasting coloured bricks
3 Use projecting bricks
4 Use contrasting, coloured or different joint finish
Use your pencil and shade in a ‘pattern’ on the front elevation, above
Wall continues
Wall continues
Plan of course 1
JUNCTION IN
FLEMISH BOND
Plan of course 2Wall continues
Wall continues
CALCULATIONS
A half brick thick wall requires 60 bricks for every square metre.
A one brick thick wall, therefore requires 120 bricks per m ²
WALL THICKNESS BRICKS PER M²
1½ 180
2 240
2½ 300
Sometimes a solid wall, built in either English or Flemish bond, may only need one ‘fair face’ side – possibly built up to a garden banking. The Stretcher bricks, used in the rear of the wall, could be a different brick to the face – possibly a cheaper brick.Solid wall bonds can therefore have a different ratio of facing bricks and common bricks, depending on the bond to be used. If this ratio is calculated it can affect the cost of the bricks for a project.
WALL 1 BRICK THICK FACING BRICKSCOMMON BRICKS TOTAL PER M²
ENGLISH 90 30 120
FLEMISH 80 40 120
TASK 1
You have been asked, by a neighbour, to work a price out for the construction of a wall around their garden.
The wall is to be built in Flemish bond, one brick thick, 15.800m in length and 750mm high.
1.Calculate the cost of the bricks, Old World Rustics, costing £327.50 per 1,000.Add 5% for breakage and wastage and also VAT @ 17.5%
Use the following page for this task – you must show all your working out.
2. When you visit the site you notice that due to their being an existing wall on the adjoining property only one side of the new wall will be seen. This now means that you will be able to use common bricks, instead of facings, to the rear of the wall. Calculate a revised price for the same wall, substituting the stretcher bricks to the rear for concrete commons @ £ 119.00 per 1,000. Add 5% for breakage and wastage and also VAT @ 17.5%
TASK 2
The wall is to be built in Flemish bond, one brick thick, 15.800m in length and 750mm high
Use the following page for this task – you must show all your working out.
These bonds are a variation of English Bond and Flemish Bond and not as the
name suggests necessarily to be used for work in or round gardens.
The 2 main Garden Wall bonds are :-
ENGLISH GARDEN WALL
FLEMISH GARDEN WALL
GARDEN WALL BONDS
English Garden Wall Bond
Draw in the arrangement for this brick bonds, on the elevation below :-
Describe the arrangement of the bricks for ENGLISH GARDEN WALL
Flemish Garden Wall Bond
Draw in the arrangement for this brick bonds, on the elevation below :-
Describe the arrangement of the bricks for FLEMISH GARDEN WALL
These 2 bonds use less headers than English Bond and Flemish Bond and are therefore a weaker type of construction.
WALL 1 BRICK THICK
FACING BRICKS
COMMON BRICKS
TOTAL PER M²
ENGLISH GARDEN WALL 73 47 120
FLEMISH GARDEN WALL 67 53 120
Refer to your calculations on Page 12 and produce a price, for the same wall, using the two Garden Wall Bonds.
YOUR CALCULATIONS
Using research techniques find TWO other bonds that can be used for solid walling.Show these bonds on the elevations, below :-
BOND
Using research techniques find TWO other bonds that can be used for solid walling.Show these bonds on the elevations, below :-
BOND
PROTECTING SOLID WALLS FROM DAMAGE BY THE EFFECTS OF THE
WEATHER
Builders are required to minimise the ingress of water into a wall and any subsequent damage caused especially from the effects of frost and ice.
Rising damp is prevented by the insertion of a horizontal damp proof course (D.P.C.), placed ideally at 150mm above the finished ground level.
The ideal material to use on an external solid wall for a horizontal D.P.C would be :2 course of Staffordshire Blue Brick
External walls must also be protected from dampness from above, such as rain. There are a variety of methods used to do this, such as :-
Brick on edge (B.O.E)
Coping
Capping
A BRICK ON EDGE (B.0.E.)
Bricks for this should be hard-burnt, dense, engineering quality.
An ideal type of this brick would be a: Staffordshire Blue BrickTo minimise the ingress of water, mortar joints must be Solid
A well-constructed B.O.E. will prevent rainwater entering the top of the wall. However the rainwater will run down the wall and cause the wall faces to become excessively damp.
To prevent this action, details are formed, such as :-A TILE CREASING-consists of 2 courses of roofing tiles (ideally Rosemary tiles), bedded in mortar, bonded and projecting over both sides of the walls face.OVERSAILING COURSE/S-Same as for Tile Creasing, only using bricks.
Neatly sketch and label end elevations showing the above 2 details.
Protecting work from damage
Think about what damage can be done to your work
and how can you protect it?
Discuss in groups
Damage Protection
Damaged cills or features Cover with a hard wearing material or special cill covers
Rain Plastic sheeting
Frost Hessian
Mortar Clean working platforms
Dust, muck or mud Sweeping up and hosing down
Wind Supporting walls using props, not building too high and backing all work up.
Accidental Signs to let people know work is taking place and barriers.
Sketch / label and describe 3 methods to help stop the end brick, on a B.O.E. being loosened, over time.
METHOD 1 METHOD 2 METHOD 3
DESCRIPTION DESCRIPTION DESCRIPTION
DRAWING DRAWING DRAWING
COPINGS-Units designed for the purpose of shedding water from the top of a wall – an alternative to a B.O.E.
Can be made from :-
A. Concrete Coping
B. Stone Coping
C. Bull nosed Brick
D. Cant Brick
Copings can be flat (paving slab) but are more efficient at shedding water if the upper surface is inclined.
There are 2 distinct shapes used :-
1. SINGLE WEATHERED
2. DOUBLE WEATHERED
Draw and label both types, laid in position on top of a solid wall.
SINGLE WEATHERED DOUBLE WEATHERED
REINFORCED BRICKWORK
Masonry is strong in compression but weak in tension. The interaction of different materials such as brick, mortar, renders and settlement of foundations can all induce stresses in masonry, which can result in cracking. The changes in weather and temperatures also can have an effect on walling.Sometimes it may be necessary to design a wall for a specific purpose e.g. a retaining wall to hold back large amounts of ground. A cheaper way than just thickening the walls width could be to insert reinforcement in between the brickwork courses.
Expamet type brick reinforcement (mesh)
Steel Welded Rod type (Bricktor / Brickforce)
Both these types of reinforcement offer an effective method for resisting both horizontal and vertical stresses than can be placed on masonry.
Any joints / laps must comply with the manufacturer’s recommendations - usually 225 mm
WELDED FABRIC