Cork Flooring 101

Photo: buildinghomegarden.com

Cork has been used for flooring for over a century. Finished cork floor can have the look of textured hardwood, the soft give of carpet, and the easy maintenance of vinyl. Throw in natural insulating and sound attenuation properties, and cork is an environmentally friendly flooring option worthy of attention.

Beneficial by Nature
A cross-section of cork resembles a honeycomb with over 100 million prism-shaped cells per cubic inch. Each cell is comprised mostly of air, making cork highly elastic and naturally insulating. Cork’s inherent “give” lets it be compressed up to 40 percent and still spring back to its original form. As flooring, cork feels softer than hardwood and warm underfoot, making it an obvious alternative to carpet.

The air within the cells also acts as sound insulation, which is why it is not uncommon to find museums floored in cork to deaden the clickety-clack of so many feet falling. “We find cork is being widely used in commercial projects like school hallways and museums, where sound reduction is important,” says Robert Sawyer of Amorim, a cork manufacturing company that makes the Wicanders line of cork floors, “but it works great in a residential setting, like a TV room, where acoustics play an important role.” In a condo requiring floors of a given impact insulation class (IIC) rating or less, cork passes the test, leaving the occupants in the unit below wondering if anyone at all is living upstairs.

Cork’s benefits come naturally, which makes it a wise choice for the environmentally conscious. It is a naturally fire-resistant material, and will not release toxins if it burns. Cork also boasts anti-microbial properties, allowing it to resist mold and mildew. Cork even naturally repels invasive insects like termites.

Design and Installation
Cork floors come in a wide variety of colors—from the more common natural-looking, honey tones to stained greens, reds, and even blacks. Cork floors can feature textures with granite-like appearances and, like hardwood floors, be installed in planks. These planks can be shuffled and arranged prior to installation to add different flows, designs, and color tones to the flooring project. The cork planks themselves will vary in actual composition from company to company, but most are layered with a cork underlayment, a high-density-fiberboard middle layer for moisture resistance, a natural cork or wood veneer layer, and a thin vinyl or acrylic finish or “wear layer” for durability and easy maintenance. “Our PVC [poly-vinyl chloride] wear layer protects from scuffs and wear,” says Sawyer. “Cleaning is easy—it’s the same as vinyl or hardwood. All you need is a damp mop.”

Although cork flooring companies offer the adhesive installation option with some of their product lines, most have turned to floating-floor systems for ease of installation. The floating-floor systems do not require an adhesive or glue be applied to the subfloor or tiles. With floating-floor systems, the tiles are laid and snapped together by virtue of locking designs that vary by name from company to company—the Wicanders line, for example, uses the CORKLOC system for its click-together, glue-free tiles. “Floating floors are fast and easy to install,” says Sawyer. “The consumer can install it easily, and there is no glue to clean up.”

A Sustainable and Renewable Resource
The cork used in cork floors comes from the bark of the cork oak, which is grown in the Mediterranean Basin, in countries like Portugal, Spain, and Italy. The cork bark is harvested from a tree every nine years, during the months when the trees are in a dormant state. The process does not damage the trees at all, and the industry is controlled strictly by the government. A cork oak is not harvested until it is at least 25-30 years old, and the trees can live for 150-200 years. Cork and cork floors are becoming a popular choice as a renewable resource in a more environmentally conscious world. “Cork is the other wood,” Sawyer explains. “People are looking for something different, for a different look.” In cork floors, consumers can finwd that different look, easy maintenance, benefits galore, plus the clear conscience that comes with using a product that is good for the environment.

Extra: The Truth About Wine Corks
Alternative wine stoppers are taking the place of natural cork in some wine bottles these days. Manufacturing companies cite a worldwide “cork shortage” as the reason for change. Sawyer says, “The shortage exists on the side of the manufacturers, who can’t get their hands on the cork as quick as they would like.”

Amorim uses cork byproducts from stopper manufacturing to make other cork products such as cork floors and cork gaskets.

The real reason for the increase in alternative stoppers may be the increase in incidents of “corked wine,” or wine that has been “tainted” by TCA, a bacteria that forms during the interaction of bad cork and wine. Alternative wine-stopper companies claim that almost 10 percent of wine in the U.S. is “tainted,” and that corked wine is the leading contributor to the $100 million annual losses suffered by the wine industry.

“Our synthetic cork eliminates the quality issues that the wine industry had with natural cork,” said one representative of Nomacorc, a synthetic cork company based in North Carolina.

Wine purists will continue to insist on wine with natural corks, however. “There is enough cork in Portugal to last 100 years,” Sawyer insists.