Cork is most widely known as a product used to preserve the quality of wine in bottles. It can also be fashioned as a board to post notes or reminders in an office. Yet, one of cork's most unique applications may leave you feeling like you are walking on air: cork flooring.
Cork flooring isn't a new concept. Cork floors have been used in the United States since around the turn of the 20th century [source: Tolli]. "It gives you sound control because it absorbs foot falls and noise," said Ann Wicander, president of WE Cork. "Traditionally, it's been used in libraries and churches, but now you see it everywhere."
The appeal of green or environmentally friendly products has prompted a renewed interest in cork flooring for the home. Many people choose sustainable flooring options such as cork floors.
In this article, we'll look at how cork flooring is created and installed along with its advantages and drawbacks as a flooring option. We'll start at the beginning with a discussion on how cork flooring is made.
The majority of cork used for flooring, as well as wine-bottle corks, actually comes from the bark of the cork oak tree or Quercus suber, native to the Mediterranean [sources: World Wildlife Fund]. The bark is hand-harvested every nine years, leaving a protective inner layer of bark that allows the tree to continue to grow and regenerate new bark. In fact, a cork tree can live to be 250 years old [sources: WE Cork].
After stripping the bark with a special hatchet and drying it in the forest for several months, the bark is transported to a factory, where wine bottle corks are punched out of the bark. The leftover material, or post-industrial waste, is boiled and ground up, then compressed using adhesive resins. This ground-up product can be cut and used as a final flooring piece or for some unique patterns, such as pieces of shaved bark used as a veneer with the ground-up material serving as the backing [source: Wicander]. Some cork flooring planks include a high-density fiberboard within them as well.
Cork floors come in a wide variety of styles offering a range of design possibilities. There are as many as 40 different colors available and shapes ranging from squares and rectangles to hexagons [source: Biscoe].
The quality of cork and the intricacy of the pattern both influence the price of cork flooring. Yet, the average cost range for cork flooring is about $5 to $12 per square foot (0.09 square meter), including parts and labor. But a lot of the cost of a cork floor depends on the quality and style. Compared to other flooring, cork flooring is cheaper than hardwood flooring and about the same as bamboo [sources: Smith, Floor Critics].
The type of flooring you choose can influence how it needs to be installed. Let's look at the two major installation methods.
Wine Cork Origins
An important component for flooring applications, the cork oak tree has also been integral to the wine-bottle cork business for centuries. The use of corks for preserving liquids has been traced back to the ancient Greeks, who used the stoppers for olive and wine jars [source: World Wildlife Fund].
How Is Cork Flooring Installed?
There are two main types of installation processes for cork flooring. The more traditional installation method, usually used for cork floors in tile form, is adhesive connection. First, the flooring tiles need to be acclimated to the environment inside the installation room. Then, the subfloor, such as cement board or plywood, must be prepped to assure that it's even, clean and free of moisture. "The adhesive application is either direct glue-down or contact method in order to fully secure the tile as it has a tendency to curl at its edges if not properly bonded," said Steven Tolli, owner of S/L Certified Inspection Services and flooring industry veteran from New York.
The floating floor installation process is preferred in residential settings for its ease and versatility. This form of installation starts with cork flooring that's specially created to provide a tongue-and-groove connection that snaps together. Unlike the exact specifications needed for the subfloor in the adhesive method, floating floor installation allows for the cork floor to be installed on top of existing surfaces such as wood, ceramic tile or vinyl flooring. It can also be easily removed and replaced as style preferences change.
It's important to note that cork flooring will react to humidity changes so you want to leave room for expansion when installing. "It's a wood product; though it's a resilient wood product," said Wicander. "It will expand and contract."
Either way you choose to install a cork floor, you can expect certain benefits from the product. We'll explore the advantages of a cork floor next.
Frank Lloyd Wright's architectural masterpiece, Fallingwater, in Pennsylvania is known for its incorporation of a waterfall into its design. Yet, the home's design further embraced its natural theme with eco-friendly features such as a cork floor and cork tiles on the walls of the bathrooms [source: Piper].
Why Choose Cork Flooring?
Cork flooring has been heralded as a green flooring option. "It's definitely more popular as people are looking for more environmentally friendly flooring," said Jennifer Biscoe, now CEO at Globus Cork.
Its environmentally friendly nature starts with the actual product and production process that are used to create a cork floor. As we said earlier, only the bark of the cork oak tree is harvested and the tree continues to flourish after the product is removed, which makes cork a renewable resource. Cork flooring can also be considered to be made from recycled content. Instead of ending up in a landfill, the waste from the production of corks is transformed into cork flooring. Finally, many companies are utilizing adhesives that are categorized as no- or low-VOC (volatile organic compounds) [source: Biscoe]. Volatile organic compounds are gases that are emitted from certain products which can adversely affect the air quality within a room [source: U.S. Environmental Protection Agency].
Along with eco-friendly benefits, a cork floor has other qualities that might lure homeowners. Several of the benefits stem from the unique structure of the cork product. "Cork, by nature, has 200 million closed air cells per cubic inch," said Wicander. Envision a wine-bottle cork. You can squeeze it, and it will condense under the pressure, but then it will bounce back to the original shape. This gives the flooring a cushioning effect under foot. The air cells within the cork also help to trap heat acting like an insulator for the floors. There is less heat loss than with hardwood floors or ceramic tiles. The air cells also make cork floors sound-resistant, absorbing vibrations. Cork flooring also has a degree of fire resistance. Due to a naturally occurring wax called Suberin within cork, the product is insect-resistant and anti-allergen [source: Globus Cork].
Cork is a durable option for flooring, but quality and maintenance can affect its lifespan. "For the glue-down, the Classic Collection, we have had it out in the market for over 100 years," said Wicander. "We have jobs that are still in service where it's been in use for over 100 years."
Now, let's take a look at the drawbacks to cork floors.
Cork Flooring Drawbacks
While cork flooring does have many benefits, it's always important to understand its limitations before making a decision for your home. First, cork flooring is not indestructible. "Regardless of what you hear, it will scratch and show indentations, specifically from high-heeled shoes," said Tolli. For this reason, it's recommended to outfit furniture feet with soft pads or coasters. Pet toenails can also be very sharp and damaging to cork floors; be sure to keep toenails clipped. Adding a coat of polyurethane and recoating every year will help to protect the cork flooring.
Another drawback to cork flooring is the potential for fading. "Unlike hardwood floors, cork gets lighter with exposure to light," said Wicander. Windows with UV-protective coatings or window coverings can help with the potential for fading.
As noted previously, cork flooring can be affected by humidity levels. This can cause the product to swell or warp with changes in moisture. It's recommended to keep the humidity levels between 30 and 60 percent to keep a cork floor looking its best [source: The Flooring Store].
Finally, cork flooring does have a cost associated with it that might be a drawback for some homeowners. If cost is a major concern, on average, cork would be more expensive than some varieties of carpeting and vinyl tiles that can be bought for $2-3 a square foot.
While cork flooring does have a few drawbacks, if you're looking for a type of green flooring with a wide range of design possibilities and unique benefits, a cork floor is certainly an option to consider.
Baker, Kermit, PhD, Hon. AIA. AIArchitect. "Residential Architects Report That Popular Home Features Focus on Energy Conservation and Accessibility." September 5, 2008. (September 24, 2009)http://info.aia.org/aiarchitect/thisweek08/0905b_hdtsq2.cfm
Biscoe, Jennifer. Marketing vice president for Globus Cork. Personal interview. September 22, 2009.