| TECHNICAL INFORMATION Composition
Bradstone reconstructed stone walling is manufactured from
naturally occurring aggregates, special blend of Portland cement, premium admixtures and
colouring pigments, the mix being regularly tested for consistency and cast in moulds. The
mould masters have been developed from natural stone in order to emulate the visual and
textural characteristics of the original material. A range of different masters is used to
avoid repetition of particular profiles and textures.
Classification
Type 1-35, Table 1, CAN 3-A165.2-M85
Applications
Bradstone walling forms the outer skin of conventional
cavity walls of traditional construction. Uses are for cladding or residential,
commercial, institutional, features and extensions to natural stone buildings where
preservation of the environment is required and all other types of construction where
stone veneer is essential. Interior applications are widely accepted for aesthetic uses.
Specification (Mortar)
Bradstone can be laid in coloured mortar, recommendations
are available. The mortar shall conform to CSA standard A 179M – 1976 "Mortar
and Grout of Unit Masonry" Type N.
Weathering
Will depend on architectural detailing, location prevailing
weather and surroundings. The introduction of damp proof coursing has had a considerable
retarding effect of the rate of weathering and lichen growth in natural stone walling and
this should be borne in mind when making comparisons. Under similar conditions Bradstone
will weather as much as natural stone.
Fire Protection
Bradstone Walling, which normally forms the external leaf
of the cavity wall, is capable of contributing to the required fire resistance for the
external wall construction as an element.
Sound Control
As a high density material, Bradstone Walling provides
effective acoustic insulation. Calculations based on the Mass Law Curve would give a
reduction of 44-46 dB in a single skin construction and a 49 – 50 dB in cavity
construction.
Frost Resistance
Test conducted at an independent laboratory indicate that
Bradstone is classified as frost resistant.
Durability
Provided that Bradstone Walling products are installed
correctly, they will provide a long low maintenance service life under normal conditions.
Bradstone has been used since the 1950s in the United Kingdom and client references can
provide evidence of the product’s durability. During winter months there may be a
risk to concrete masonry from the increase use of de-icing salts from roads and pavements
in close proximity. Moisture movement and the migration of soluble salts makes frost
action more aggressive and may result in degradation.
Testing
To ensure a consistent level of Quality, Bradstone products
are subject to a regular testing programme in order to provide characteristic design data
and product information.
Results
Cylinder Strengths of Mixes:
The compressive strength of Bradstone mixes exceeds 35 Mpa
at 28 days as tested in accordance with CAN.3A23.2-M77.
Density of
the final product is in the range of 2250-2350kg/m3 of face work.
Absorption
the 24 hour rate has been found to be approximately 4% by dry weight. Initial rate of
absorption (IRA) is approximately 5g. which is well below the normally accepted maximum of
20 g. tested in accordance with CAN.3-A82.2-M78
Shrinkage can
be expected to average 0.03%.
Heat Transmission Value,
The Value for the heat transmission of Bradstone is to be taken as R0.44 |
