Suberin is a waxy substance found in the bark of the cork oak tree and that is named after the Latin for the cork oak – Quercus suber.
The distinctive property of suberin is that it is hydrophobic, or in other words, water resistant. Plants and trees contain suberin because they need some way to regulate the water supply. For example, mangroves contain suberin to limit the amount of salt they take from their littoral environment.
In the case of the cork oak, suberin is found in the phellem or outer layer of the bark and stops the tree losing moisture. The cork oak tree grows nearly exclusively in the Mediterranean area where there are long spells of dry weather.
The bark of the cork oak can be peeled off the tree without damage. In just 9 years the tree has grown another bark. The second harvest and subsequent harvests of bark are much more uniform and suitable for making cork flooring.
Because of the suberin in cork flooring, it is water resistant. The waxy substance prevents water from passing through the flooring. This means that if you spill water on cork flooring the water will sit on the surface. Of course, a lot of water will penetrate cork flooring eventually and if water is left standing on the cork flooring it will damage the flooring.
Another benefit of suberin in cork flooring is that it makes the flooring fire retardant. It is very difficult to set fire to cork and in the event of a fire, cork flooring does not give off any noxious gases.
Finally, suberin in cork flooring is a repellent against numerous insects and has been shown to have antimicrobial properties. This makes cork flooring and cork underlayment ideal for people who suffer from allergies or asthma.
Cork flooring is not only from a renewable resource and thus sustainable flooring it is also healthy flooring.