Colinwell
bricks are manufactured by blending and compacting crushed
aggregates, cement (and in the case of facing bricks, pigments)
and moulding under high pressure with particular attention being
given to achieving accurate dimensions, high strengths and good
fire resistance.
The bricks are generally solid, or perforated in the case of some
facing bricks.
Four categories of bricks are produced in a range of strengths and
finishes.
Common bricks, Lightweight bricks. Facing bricks and
Engineering quality bricks.
In certain cases bricks may be produced to order with a
sulphate resisting cement to ensure high durability when subjected
to aggressive ground conditions. |
Approval
All bricks are produced in
accordance with BS6073: Part 1. 1981. However, the specific
requirements for strength, sulphate resistance and durability also
satisfy the following references:
a) BS 5628: Part 3. Structural
use of concrete masonry.
Scope: Refers to quality of masonry for
durability / workmanship and design.
b) Building Research Establishment Digest 250 "Concrete in
sulphate bearing soils and groundwaters."
Scope: Covers the recommendations of cement type
and concrete quality, to resist attack by naturally occurring
sulphates.
c) BS 8301:1985 "Building
drainage".
Scope: Recommendations for design, layout and
construction of foul sewerage, surface water and ground water
drains ... works described are likely to be met in housing, public
buildings, schools and industrial buildings.
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Technical Specification
Composition & Application
|
Standard
and High Strength Common Bricks, Fair-Face Bricks
Crushed aggregates and ordinary Portland Cement
Common bricks are available in a range of strengths and are
suitable for general construction above and below ground level.
Fair-Face Bricks will provide an acceptable face, particularly if
built fair or painted. If it is intended to use the bricks in this
manner it is essential to specify the bricks for this purpose
before ordering. |
Engineering
Quality Bricks |
Crushed
aggregate and Ordinary Portland
Cement.
Engineering quality bricks can be used in particularly aggressive
conditions where low porosity and water absorption are paramount.
Typical locations such as manholes and inspection chambers can
adequately be constructed using these particular bricks. |
Sulphate
Resistant Bricks |
Crushed
aggregate and Sulphate Resistant or Portland Blast Furnace Cement
Sulphate Resistant bricks are intended for areas where structural
loadbearing properties may be important but where resistance to
sulphate attack from groundwaters or soils is essential. They can
be produced to perform in up to Class 3 sulphate conditions. |
Lightweight
Bricks |
Graded
Pumice Aggregate and Ordinary Portland Cement
Lightweight bricks are used in conjunction with lightweight blocks
to eliminate cold bridges, reduce block cutting and provide a good
background for nailing and fixing. |
Facing
Bricks |
Crushed
aggregate, Ordinary Portland Cement and Pigment
Facing bricks provide an attractive appearance for use in all
forms of internal or external construction. They are available in
a spectrum of colours including multi-colours and a range of
finishes and textures |
Form |
| Bricks
are produced in solid, or perforated form in the case of some
ranges of Colinwell Facing brick. |
Size,
Weight & Coverage |
All
bricks are made to the size below. The approximate weight (kg) of
each brick is indicated. The number of bricks built is based on a
single leaf (10Omm) wall with 10 mm joints.
LENGTH: 215 (+/- 2mm) WIDTH: 103 (+/- 2mm) HEIGHT. 65 (+/- 2mm) |
|
Density & Thermal Conductivity (approx.)
|
|
Strength Category
|
|
| Higher
strengths, up to 42 N/mm² (Class 6) are available in most brick
types except lightweight pumice. |
Water Absorption
|
| Absorption
is not a mandatory requirement in BS 6073 Part 1 as there is no
relationship between absorption and durability on concrete bricks.
However, as guidelines for suction rates and other calculations
the following data is provided. |
|
Drying Shrinkage
|
| The
drying shrinkage is measured according to BS 6073. However, it
should be borne in mind that under permanently damp conditions
drying shrinkage may not occur. |
|
Aesthetic Properties
Finish
|
| Facing
bricks are produced in a choice of textures whilst common bricks
are only available in an open textured finish. |
| Colour |
| Common
bricks can be variable in colour and texture, whilst facing bricks
are produced in a wide diversity of colours. The colours are
stable, consistent and dispersed throughout the body of the brick.
Each mono and multi-coloured
facing is given an individual name and customers should refer to
these names when specifying or ordering.
|
Functional
Performance
Acoustic Performance |
| The
average sound reduction coefficient for plastered single leaf
partitions, when calculated over a frequency range of 100 - 3150Hz
gives results between 44dB and 50dB dependent on the wall
thickness.
Colinwell dense bricks are
particularly suitable for the reduction of airborne sound
transmission and, therefore, should be used for the construction
of party and separating walls.
The constructions illustrated
satisfy the correct Building Regulations.
|
Fire
Resistance |
| Lightweight
and some facing bricks are manufactured using a Class 1 aggregate.
Class 1 bricks have a performance when subjected to fire, details
of which are given in the following table.
Some facing bricks may be
produced using a Class 2 aggregate which may give slightly reduced
values.
|
|
Cavity
walls
Two leaves of dense brick 50 mm cavity. Wall mass >430 Kg/m²
Solid walls
215mm wall, plastered on at least one face Wall mass >430 Kg/m² |
Site Information
Storage |
| Bricks
should always be stored clear of the ground on a flat level
surface and protected against snow and rain. Incomplete work
should also be protected from the elements. |
Construction
|
| Building
and storage techniques should be in accordance with the
recommendations given in BS 5628. Part 3. "Structural
use of concrete masonry", especially with regard to party
wall construction, site protection and movement control.
Manholes and inspection chambers
should be constructed using Engineering Quality bricks in
accordance with BS8301. 1985. "Building drainage".
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Cavity Insulation
|
| Because
of the impermeability and low water absorption of Colinwell facing
bricks, consideration should be given to the choice of thermal
insulation which may be used in cavity walls..
Mortar joints may allow rain to
pass into the cavity. Users should be aware of the restrictions on
certain forms of cavity fill in areas of medium, or high exposure.
Generally Colinwell recommend an insulated wall system which
maintains a clear cavity of at least 50mm.
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Plastering
|
On dense bricks i.e. commons Carlite
Bonding Coat
On lightweight bricks
Carlite Browning
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Rendering
|
On common
brick and lightweight brick the mix should be between 1 : ½ : 4½
and 1: 2 : 8 cement : lime : sand.
In all cases rendering should be carried out to the thicknesses
and recommendations given in BS 5262:1976. |
Specification Clauses
|
Specifications should read as follows:
The bricks for use in (location) should be Colinwell (name, finish,
type) of (N/mm.) minimum strength, produced and supplied by Colinwell
Concrete Ltd.
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