understanding cork flooring

About Cork

cork plantCork is a wonder of nature: it grows only on one tree, the cork oak tree, Quercus Suber L!

Cork oak plantations cover approx. an area of 2.5 million hectares, basically in Portugal (with has more than 52% of the world production) and other countries along the Mediterranean basin, being the main ones: Spain (26%), Italy (7%), Morocco (6%), Algeria (5%), France (3%) and Tunisia (2%).

The "Cork Tree" (oak) has a lifespan of 200-250 years. The first harvest occurs when the tree is between 20 to 25 years old and provides the so-called "virgin" cork. The "virgin" cork has a hard and irregular structure and not suitable for natural cork stoppers production, though it is an important raw material for many industrial compounds.

After extracting the “virgin” cork a new layer of cork starts growing and it takes approximately 9 years for this layer to reach the desirable and necessary thickness for it’s primary application, the production of Natural Cork Stoppers. This second crop is called "secondary cork" and the ones thereafter as "amadia".

During its lifespan, a Cork Tree allows about 15-16 harvests repeated every 9 years, producing hundreds of kilos at each crop and survives in a very poor climacteric environment. The cork stripping is assured by skilled labor and does not harm the tree in any way, being a vital process for the tree’s reinvigoration.

Cork production is guaranteed with new re-plantations every year. Trees are never cut down or removed without government permission, which supervises and regulates this activity.

In fact, Portugal and more recently also Spain and other producing countries have been particularly careful with its cork forests. Portuguese regulations protecting cork oak trees date from the 14th century and have been reinforced during the last years. Cork, a true environmentally friendly product!

Types of Cork

  • Granulated Cork
  • Agglomerated Cork
  • Cork Flooring
  • Cork Wall
  • Rubbercork
  • Insulation
  • Others

What is Cork?

cork barkCork is the outer bark of the cork oak tree, Quercus Suber L, a vegetable fabric formed by millions of micro-cells (one cubic centimeter/0.06 cubic inches can contain over 40 million cells) these cells are filled with a gaseous mixture identical to air.

inner layers of corkThere are five inter-cellular layers: two are cellulose, two are formed by suberin and wax and the fifth is woody providing the necessary structural rigidity. The presence of suberin makes the cork impermeable to liquids and gases, which together to its elasticity ensures great usefulness to satisfy many different kinds of industries.

cork cell structureThis cell-like structure, like a honeycomb, gives cork great elasticity and, as incredible as it may seem, cork can be compressed to half its size without loosing any flexibility.

The cushion-like cells have a veritable elastic memory. When compressed, they instantly try to return to their original shape. This elasticity gives cork a high level of tolerance to climacteric changes. It’s light, chemical inertness, resists moisture and it's biodegradable.

The properties of cork derive naturally from the structure and chemical composition of the extremely strong, flexible membranes that are waterproof and airtight.

cork usages 

General Applications

Ever since the V century B.C., Cork has been used as stopper on amphora for sealing wines. Later by 1680 used for the first time by the monk Don Pérignon to seal Champagne and from those ancient times until now, it has evolved into a versatile material used in several activities. From Baseballs to bottle-stoppers, to the heat shield of Space Shuttles, few naturally renewable materials can touch our lives so frequently as Cork.

Many of its uses are probably not known by the majority of us because they may be not visible to our eyes but yet its benefits are remarkable and outstanding. Cork unique properties available in many different shapes: Natural, Granulated, Agglomerated in blocks, sheets or rolls and in combination with other materials and unique formulations, make today’s living safer, more enjoyable and comfortable!

Properties of Cork

Cork most distinguished and useful properties are:

  • Low Density – due to the gaseous inside it’s cells, cork is extremely light
  • Resiliency – as cork is elastic at a cellular level, it’s also very resistant
  • Impermeability – the cellular membranes are waterproof protecting the cork from moisture
  • Insulating and Fire Retardant properties – prevents the quick spreading of fire
  • Low Conductivity – preventing electrical risks, especially in factories
  • Highly Resisting to wear and tear – allows its products to be wear-resistant
  • Warm to sight and touch – natural cork has a soft, porous and dry touch
  • In its several forms, cork always has appealing color patterns
  • Anti-Static preventing electrical risks, especially in factories

cork tree plantation

What is Cork Used For?

Cork properties make it an all-purpose problem solver and suitable for a wide range of applications:

  • Energy Conservation
  • Flotation
  • Gasketing
  • Insulation
  • Load Bearing
  • Polishing
  • Sealing
  • Sound Dampening
  • Vibration Control
  • Weight Reduction

The above lists only few of the most common applications for Cork, but everyday new applications are discovered and builders, architects, engineers, scientists, fashion designers, interior designers and manufacturers of house-wares, sporting goods and leisure products select Cork due to its naturally renewable characteristics, for their exclusive and most demanding applications and for its biodegradable and environmentally friendly attributes.