Stamped concrete | What is it?

Stamped concrete is the result of an embossing and texturing process that’s currently gaining many fans around the world.

This is due to the remarkable aesthetic benefits it grants concrete surfaces, accompanied by appealing economic benefits.

Stamped concrete also stands out for keeping the concretes most important properties intact. That is, its resistance and durability, requiring only a simple maintenance to guarantee its functionality in high traffic areas.

What is stamped concrete?

Este tipo de hormigón se refiere a la técnica decorativa de aplicar un “mortero endurecedor continuo” realizado “in situ” sobre una superficie de hormigón fresco. Normalmente en algún color y textura.

Su principal función es completamente estética, valiéndose de la plasticidad de la mezcla durante el proceso de fraguado. 

To achieve stamped concrete, the appropriate pigment must be spread on the fresh concrete surface, and then the moulds must be placed, which will be pressed against the concrete.

Las formas elegidas se realizan con diferentes moldes, normalmente definidos por formas geométricas o imitaciones de madera, piedra, ladrillos, baldosas, adoquines, etc.

La técnica del hormigón impreso se finaliza con la aplicación de una “resina” que ofrecerá protección al pavimento.

The advantages of stamped concrete

Most of stamped concrete’s characteristics are, in practice, considered to be an advantage because it doesn’t vary the concrete in any way, after the setting and curing processes.

Sin embargo, no se debe olvidar que es un tratamiento estético para otorgarle atractivo superficial y sofisticación al hormigón corriente y que las ventajas vienen principalmente del producto del hormigón en sí.

Here we highlight some of the most important stamped concrete advantages:

• High mechanical resistance to relatively frequent traffic.
• Durability.
• Waterproof.
• They have the ability to be anti-slip.
• Resistance to solar ultraviolet radiation.
• Thermal resistance to sudden fluctuations, especially during frost and thaw.
• It can be used in large lengths of continuous paving.
• El tiempo de ejecución es reducido, en comparación con otros procesos de acabado.
• Maintenance almost null, due to its simplicity.
• They have a wide selection of shapes, colours and designs.
• Molecular stability against the attack of aggressive and abrasive chemical substances, such as acids, fats and oils.

Stamped concrete floors are often compared to polished concrete floors, as both have effective results and provide an optimal surface for transit.

Esa comparación de pavimentos se refiere solo a esos resultados efectivos, porque el suelo de hormigón impreso y el suelo de hormigón pulido son 2 tipos de suelos que se usa para diferentes tipos de construcciones.

Concrete stamping

Antes de proceder con el estampado de hormigón es preciso establecer algunos aspectos preliminares relacionados con la superficie del suelo, el colorante y la resina para hormigón impreso a usar, todos ellos explicados en estos puntos:

• The base must be stable against any external influences, as well as being properly levelled and compacted.
• The floor base mustn`t affect the concrete’s mechanical resistance or its volumetric stability. Furthermore, it must be chemically compatible with lime, but without being susceptible to decomposition during the setting process of the cement.
• It must provide uniformity to create regular colourings. Likewise, it must contribute to the rigid flooring’s surface resistance.
• The colouring mustn’t affect the properties of the concrete. Being stable and chemically compatible.
• The resin must fill the pores of the concrete to seal its surface, generating a durable and resistant layer to thermal changes and abrasion.

Now, regarding the concrete, it is worth taking into account:

• Its resistance must be higher than 220 kgf / cm2. In the worst case, a minimum compressive strength of 200 kgf / cm2 is allowed.
• The maximum value of the water / cement ratio should be 0.55, to avoid the adverse effects of shrinkage.
• The consistency of the concrete needs to be soft.
• It’s recommended that water used for mixing should be clean and potable, without traces of sulphates and carbohydrates.

Stages to stamped concrete

Once all the important preliminary aspects are known, it should be known that the stamped concrete process is mainly done in 3 steps, the first 2 consist of colouring processes and the last one, stamping.

Base colouring

To stamp the concrete, you first have to add the base colouring, which will be the primary colour that gives a natural appearance in order to achieve the coating which we want to replicate.

The base colouring is created by adding hardening colouring to the concrete, this is a powder pigment.

There are 2 ways to do the base colouring. The first is an integral coloration, in which the entire volume of concrete is coloured, whereby the pigment is added during the mixing of the concrete.

The second option consists of applying the pigment on the surface of the flooring, in a plastic state.

Definitive colouring

In order to achieve the desired colour, a second colouring is needed. This second colouring is a pigment that’s responsible for texturing and adding a more detailed finish, it’s also non-stick, making it impossible for the stamping moulds to stick to the surface.

Like the previous stage, to apply the dye there are 2 ways of doing so, in accordance with its state, since it can be a powder or a liquid (solvent).

Powder colouring is the most commonly used product, which only needs to be spread on the surface before stamping. The liquid pigment is part of the content of sprays, so it is sprayed on the molds, prior to stamping.

Stamping

Esta última etapa consiste en la colocación a presión de los moldes, cada uno con un patrón geométrico particular, siendo normalmente la imitación de algún material de recubrimiento, como madera, baldosas, adoquines, piedra, pizarra, entre otros.

The moulds are generally made of polyurethane, although neoprene has recently been used, since it’s a material with greater versatility to simulate more varied shapes.

To finish the stamped concrete floor, resins are used to seal the entire surface of the concrete, to enhance its water resistance.

Video explicativo del proceso

¿Cuál es el precio del hormigón impreso?

Lo primero es saber que el coste del hormigón estampado se presupuesta por m2 ejecutado (mano de obra y materiales) y los bordillos en cambio se presupuestan por metro lineal.

El precio medio del hormigón impreso de 14 cm de espesor se sitúa entre los 25€ – 35€ el m2

Si este precio se encuentra dentro de tu presupuesto, pide varias ofertas a diferentes empresas. Eso si, te recomendamos que descartes aquellas que no te incluyan en el precio el refuerzo con una armadura, mallazo o fibras. Es decir, la instalación es conveniente que sea reforzada.

Aquí puedes conocer más sobre el hormigón reforzado con fibras metálicas.

How to maintain stamped concrete floors?

El mantenimiento es un punto clave de las bondades del hormigón estampado, ya que la superficie tiene una resistencia y durabilidad tan elevada que hace casi innecesario realizar cuidados en el hormigón.

No obstante, los pavimentos deben estar sometidos a una revisión periódica, para renovar los tratamientos superficiales, ya que la probabilidad de defectos nunca será del todo nula; las juntas son los elementos estructurales a los cuales hay que tener mayor consideración.

Restorations are recommended to compensate for the accumulated abrasion.

Even the cleaning of the flooring must never be neglected, since spills of harmful liquids, such as oils, may occur, which can damage the appearance of the concrete. Also, the removal of miscellaneous dust and debris is necessary.