Sustainable Flooring Options: Cork, It’s Not Just for Wine Bottles

Posted on August 5, 2008
Tag(s): Green Furnishings, Green Building | | Email this

This week, I’ll be writing about various sustainable options for flooring beginning with cozy, comfortable cork.

Cork is the bark of the cork oak tree, grown mainly in the Mediterranean. Harvesting includes not cutting down the tree, but by removing (by hand) about 50% of the bark and drying it for a period of 3-6 months. During a cork oak tree’s lifespan of 150-200 years, it is ready for harvesting in its 25th year, and then every 9 years thereafter. Chemical pesticides and fertilizers are not typically used in cork forests.

Cork was the first resilient flooring and was very popular in the early 1900’s. There has been a resurgence of interest today due to it’s sustainability and longevity. Many of the cork floors from the 1920’s and 30’s are still in use today. Cork flooring has a unique structure and consists of 80% air. This allows it to recover up to 100% of its original dimension even when compressed by table or chair legs that are properly protected. It is comfortable underfoot, resists scratching and staining, reduces sound transference, is easily maintained with a damp mop, is non-toxic and does not emit odors or chemicals. Cork flooring can be used to achieve LEED credits through the United States Green Building Council.

A Pennsylvania-based company, Expanko, adheres to the highest standards using traditional methods of the past in conjunction with new advancements in production. “To produce cork flooring, virgin cork bark and cork waste from the manufacturing of other cork products is recycled and ground into small granules. The granules are baked in molds at varying temperatures, allowing shade variations, from light to dark, in the finished tile product. Being a natural product, shade variations are inherent. After being baked, cut into slabs, sanded and finished with our natural wax or polyurethane, the tiles are hand-sorted.”

Expanko offers cork tiles in 12″ x 12″ and 24″ x 24″ sizes that are either 3/16″ or 5/16″ thick. Custom sizes are also available. Tiles are offered in factory-applied polyurethane or natural wax finishes.

It can be easily installed (by an experienced hardwood or tile installer) over a concrete or plywood subfloor and is suitable for both residential and commercial applications. A water-based, zero-VOC adhesive is used to install the tiles. After the tiles are laid, they must be rolled with a 100 lb., 12 inch wide roller. Periodic resealing aids in resisting fading from UV rays of direct sunlight. Expanko exclusively uses a UV-inhibiting finish and recommends using windows with a UV protective coating, as well as window treatments. Sanding and refinishing of cork floors is not only possible, but will restore its original color.