Portugal is not only known for good wine and beautiful beaches, it is also the largest producer of cork, more than 50% of the world supply comes from this country.
Natural cork originates from of the bark of the cork oak tree (Quercus Suber), which is indigenous to the mediterranean region and northern Africa. The first harvest of a tree can be made after approximately 25 years and the bark renews itself naturally every 9 to 12 years.
The cork oak forests in Portugal, called Montados are an important contribution to the biodiversity and maintaining the balance in the ecosystem. It is important to preserve these forests, because it is home to a number of mammals, reptiles, birds as well as the Iberian lynx, the world’s most endangered feline species. The montados are part of the Portuguese cultural heritage and contribute to the regional identity.
Cork has some remarkable qualities and can be used for many different purposes, it is even applied in space as thermal insulator for space shuttles. It is light, wear resistant, elastic, liquid-impermeable, fire retardant and has great insulation properties. Furthermore, it is 100% reusable. The structure is composed out of tiny gas-filled cells, which eventuates in a huge disproportion between the volume and the weight of the material, more than half of its volume is air.
These properties make cork incredible useful as building material, whether as flooring, insulation sheets or surface finish.
If the material is used raw and 100% natural, it can provide an ecological alternative to conventional solutions, not least because of the barks ability to absorb CO2 during the regeneration process. Regularly harvested cork trees store 3 to 5 times more CO2 than those left unharvested.
Apart from all these seemingly eco-friendly features, the industry of cork can also have some downsides.
Cork is indigenous to the Mediterranean region, if used outside of Europe or Africa, the high amount of fuel used for shipping the material around the world, makes it questionable whether the use is as „green“ as it seems.
Furthermore, some cork products, especially those used for flooring, contain chemical binders, finishes or substrates. Sometimes the cork is combined with Polyvinyl Chloride (PVC) to make resilient flooring much like linoleum. Other significant factors to consider are the dyes, binders, adhesives and/or finishes used in the manufacturing or installation processes for cork flooring.
Have a look to this links to find out more about the material, producers and projects with cork: