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Clayworks External Finishes

Clayworks External Finishes

Clayworks Ltd

Natural mineral wall finish in custom colours and textures. A hydraulic lime (NHL)-based cement-free render product suitable for external application.

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+44 (0)1326 341 339 www.clay-works.com

Application

Suitable for external rendering mortar and external coloured rendering mortar.

Description

Clayworks External Finish (CEF) is a natural mineral wall finish in custom colours and textures. A hydraulic lime (NHL)-based cement-free render product suitable for external application.


The product has been formulated by Clayworks to complement the company’s primary range of Clay Plasters which are not suitable for external use. CEF is manufactured utilizing a responsibly sourced controlled blend of lime (NHL) to EN 459-1, carefully selected aggregates with the addition of natural inert mineral pigments if specified. The unique properties of this render make it suitable for the external application on various density substrates, for renovation of old and listed buildings and ecological new builds.


The active NHL ingredient conforms with British Standard EN 459-1: 2015 ‘Building Lime. Definitions, specifications, and conformity criteria’, which is applicable to building limes used as binders for the preparation of mortar for masonry, rendering and plastering and the production of other construction products. The product's special composition allows the product to breathe and also permits constant hygrometric exchange between the substrate and the environment. The pre-mixed 25 kg bags of Clayworks External Finish render is 100% natural and ready to use.


The NHL element is manufactured by calcinating a high calcium limestone in carefully controlled conditions at a temperature of around 1200°C. The quicklime produced is then crushed and hydrated to produce a fine powder with a approximate bulk density of 650 kg/m³. The NHL so utilized in the production of CEF is ISO 9001 certified.


The CEF pre-mix render product is factory supplied and quality controlled.


Features and benefits:

  • Non-combustible: as tested by the British Research Establishment (BRE) in accordance with BS 476-7:1997.
  • 100% natural.
  • Durable.
  • Breathable.
  • Flexible.
  • Colour consistent.
  • Less susceptible to sulphate attack.
  • Environmentally friendly, as lime renders actively absorb CO2 from the atmosphere.
  • Highly resistant to freeze thaw.
  • Factory supplied and quality controlled.
  • Easy to use, just add water.

General information

Shape

Seamless.

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Color

Available in any colour, custom created to designer's requirements.

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Finish

Custom finishes to designer's requirements. From smooth, to textured, to carved to rammed earth effect.

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Material

Hydraulic lime

Hydraulic lime (NHL) based cement free render.

Size

25 kg bags; seamless finish.

Uniclass

Pr_35_31_64_48 Lime rendersPrimary

CAWS

M20/42 Multicoat proprietary plaster

M20/330 Proprietary lime:sand

Specification data - Lime renders Enhanced data

Components

Hydraulic lime.

Mix

1:2.5 (lime:sand).

  • The approximate coverage is approximately 1.5 m²/25 kg bag.
  • 87% sand by weight (@ 1800kg/m³).
  • 13% NHL by weight (@ 650 kg/m³).

Lime notification

To BS EN 459-1.

Sand

Course and fine.

  • Aggregate type 1: is a fine angular well graded 2 mm down to 75 microns flint type (52% by weight of the total).
  • Aggregate type 2: is a coarse angular well graded 5 mm down to 75 microns flint type (35% by weight of the total).

Colour

Available in any colour, custom created to designer's requirements. Options include include colour ombres and rammed earth effects.

Consult manufacturer and insert requirements.

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Textured finish

Custom finishes to designer's requirements. From smooth, to textured, to carved to rammed earth effect.

Consult manufacturer's literature and insert requirements.

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Reaction to fire

To EN 998-1:2010, A1.

Water absorption

Capillary water absorption.

To EN 998-1:2010, Class W0.

Water vapour permeability

To EN 998-1:2010, 15/35 μ.

Adhesion

Adhesion (N/mm²) and fracture pattern.

To EN 998-1:2010, ≥0.05 N/mm².

ThermalConductivity

To EN 998-1:2010, 0.83 W/m·K.

Environmental information

Contains Red List materials

No

Country of product manufacture

United Kingdom