Cast stone products manufactured by UKCSA Full Members to the Association’s stringent requirements and specification are already supplied to a standard in excess of the BS 1217 requirements.
However, the UK Cast Stone Association agreed at its January 2013 Executive Committee Meeting to introduce its own Quality Mark standard for cast stone, which all UKCSA manufacturing members will be required to comply with as a condition of their membership.
The Association’s work on the Quality Mark Scheme is now complete and from 1st May 2013 if users and specifiers of cast stone require further reassurance that the cast stone they are using is durable and produced to the highest standards, then they should look for the Quality Mark label on the cast stone.
The UKCSA Quality Mark label will only be available on cast stone which has been purchased from an UKCSA Full Member. The inclusion of a Quality Mark label on cast stone is the UKCSA manufacturing member’s confirmation that the cast stone supplied complies with all of the Quality Mark Scheme requirements.
Aspects of cast stone which are covered by the UKCSA Quality Mark Scheme include:
Cast Stone Manufacturer’s Details
The name and contact details of the UKCSA manufacturing member who is certifying that the cast stone conforms to all requirements of the UKCSA Quality Mark Scheme shall be stated on the Quality Mark Label.
Material Type
The manufacturer shall state the cast stone material type, which shall be either dry-cast cast stone, wet-cast cast stone or fibre reinforced cast stone.
Cube Compressive Strength
The cast stone shall have a minimum cube compressive strength of 35 MPa, which represents a strength at least 40% higher than the BS 1217 requirement.
Dimensional Tolerance
The dimensional tolerance of the cast stone shall be in accordance with the UKCSA Specification / BS 1217, Clause 8.1.
Flatness of Plane
The flatness of plane of the cast stone shall be in accordance with the UKCSA Specification / BS 1217, Clause 8.2.
Weathering Grade
The permeability and durability of the cast stone, when tested in accordance with the Capilliary Absorption Test (CAT) shall not exceed 1.0 mg/mm2.
Download UKCSA Guidance Note: Capillary Absorption Test (CAT).
Durability Against Freeze / Thaw
Products complying with these requirements are deemed to be freeze / thaw resistant.
Bond Strength
In accordance with BS EN 998-2 for general purpose mortar – the Characteristic Shear Strength is 0.15 N/mm2.
Thermal Conductivity
In accordance with BS EN 1745 – λ value for cast stone is in region of 1.2 to 1.7 W/mK for a 5% moisture content product.
Reaction to Fire
Cast stone products shall be in accordance with Euroclass A1 requirements.
Acceptability of Surface Finish
Acceptability of surface finish shall be in accordance with the UKCSA cast stone acceptability guidance.
