CONCRETE is visible is brick. The architectural precast concrete cladding here is brick-faced with a layer of half bricks embedded into the concrete. Brick-faced concrete cladding panels combine the aesthetic of brick with the benefits of concrete and offsite manufacture, offering complex and intricate brick detailing that is otherwise challenging to achieve in mainstream contemporary construction. It may even be a means of affording a higher quality brick through resource-efficient use of both sides of the half bricks. Similar benefits are offered by casting natural stone into the face of concrete.
But perhaps the most unique aesthetic benefit that concrete can offer is its ability to be cast into almost any shape, curve or surface relief. Once the effort has been made to create a bespoke shape and form it is possible to repeat it again and again. The pre-casting process of concrete thereby facilitating the repetition of even the most elaborate decorative features. And with contemporary processes of digital scanning and routing, the creation of bespoke moulds and textured linings is even more cost-effective.
2 techniques applied to the surface. Interesting effects and patterns can be cost-effectively created on a single cladding panel simply by using different surface treatments. Techniques include acid-etching and abrasive blasting that lightly remove the smooth outer surface of the concrete to reveal the fine grain and colour of the aggregate in the mix. Heavier and deeper applications create a different tone, with more defined texture as more aggregate emerges. By contrast the concrete can also be smooth and reflective. Large horizontal surfaces are safely and cost effectively polished in the factory. The more concrete that is removed through grinding and polishing, the wider the cross-section of aggregate that is visible.
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Another common technique to create texture is the use of surface retardants. Applied to either the face of the formwork or to freshly struck concrete, the retardant prevents the surface laitance from hardening, so it can simply be washed or brushed away to reveal the sand and stone aggregate within. Precise, repeatable patterns, even photographs can be permanently created in the face of the concrete using patented techniques that print the retardant on to a form-liner in the required pattern, creating contrast between exposed aggregates and adjacent smooth surfaces. A recent project, Cartwright Gardens, London provides an example of effective and attractive precast concrete, although the material that
Aesthetics are sometimes seem as limited with a catalogue approach to offsite construction. Choosing architectural precast concrete provides an offsite solution for structural precast and architectural cladding that can be bespoke and beautiful. As well as providing the inherent performance benefits associated with concrete solutions. For more information visit: www.concretecentre.com
Image: 01. Brick faced concrete cladding panels at Cartwright Gardens by Maccreanor Lavington. Precast supplier Thorp Precast. Courtesy Thorp Precast 02. Bespoke architectural precast cladding combining polished and acid etched surfaces. Victoria Gate, Leeds by ACME. Precast supplier Techrete. Courtesy Techrete
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