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Cork in sustainable construction industry

As an ecological and sustainable material, cork is not only intended to end up as a bottle stopper. Thanks to its many advantages, it is one of the trendy materials when building an ecological house. From insulation to cladding, discover cork in all its forms! 
A 100% ecological Portuguese heritage

Cork comes from the bark of the cork oak tree, which is found in Portugal as well as in the Mediterranean basin. Thanks to its favourable climate and know-how, Portugal has become the world’s largest cork producer, accounting for 49% of world production, according to the Associação Portuguesa da Cortiça (APCOR).

Cork is considered as a natural material because the removal of the bark from the tree doesn’t imply cutting or damaging it. The bark regenerates naturally and is removed approximately every nine years. Once processed, the raw material is intended to be marketed in different forms: as cork stopper or as a building, decoration and design material.

A high-performance thermal and acoustic insulation material

There are two types of cork as insulator, agglomerate composite cork and expanded cork. The difference between the two is in the transformation process: the first requires additional components for the binder, which can be eco-friendly, while for the second it is the natural resin, suberin, which is heated at high temperature to act as a binder. Expanded cork is marketed in the form of board or granules. Agglomerate composite cork is also available in the board form or rolls.

Expanded cork © Amorim Cork Insulation

Cork can then be used as acoustic insulation, anti-vibration or thermal insulation applied in walls, roofs, formwork or even facades, in the case of expanded cork.

This insulation material has many advantages: good thermal conductivity, unlimited lifespan, promotes good indoor air quality, water, insects and rodents resistant and excellent acoustic insulation.

The trend of cork as a cladding

Too long seen as a cheap looking material, cork is making a big comeback as a decorative panel!

It can then be used as a floor covering, a particularly comfortable option thanks, among other things, to its insulating assets. Cork flooring is easy to maintain and gives a warm aspect to the room. Healthy and sustainable, it can be a good option in case of respiratory allergies.

Cork can also be used on interior walls and brings an ecological touch to interiors. The trend is, for example, on a cork wall in the bathroom, as a kitchen splashback, or as a head-board in the bedroom. In case of wall interior cladding, cork can be found in panel.

Wall cover © Amorim Cork Insulation

Finally, cork and its eco-friendly style found a place in the field of design, with brands of cork furniture and cork decorative accessories.

3 questions to Carlos Manuel Silva, CEO of Amorim Cork Insulation – Portuguese manufacturer of expanded cork insulations

Am I guaranteed to have a 100% natural insulation if I choose expanded cork?

We only use cork (a natural and renewable raw material), in an industrial process that consists of heating at high temperature, followed by a period of stabilization of the blocks, again without any type of treatment. This agglomerate expanded cork is indeed 100% natural. It should also be noted the low energy consumption, namely 10% fossil energy and 90% biomass resulting from the process itself.

Does cork as a decorative covering provide additional thermal insulation?

Even for decorative coverings, the properties of cork do not change, i.e. it works as a thermal insulation material and has excellent acoustic behaviour.

How is expanded cork insulation suitable for passive construction?

Perfectly adapted to the passive construction concept, this material has excellent thermal performance, with almost no alteration of its performance when subjected to thermal variations, thus improving its longevity/durability while maintaining its level of efficiency. There is a lot of concrete examples, especially in the case of passive construction, such as installations dating from 1995 in harsh climates, where expanded cork remains perfectly intact/effective. Another element to be highlighted is the fact that after demolition of the building the cork can be recycled and reused in its entirety.

Would you like to know more about sustainable construction in Portugal? Download for free our white paper!

Photo: maja7777 on Pixabay

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