Cork flooring is prized for its natural wood look and its cushiony, warm feel underfoot. It's also largely made with natural materials and is one of the more versatile flooring options, suitable for most areas of a home. Like many types of flooring, cork is available in easy-to-install planks that click together to create a "floating floor" that needs no fasteners or glue. This makes cork popular with DIYers on a budget who plan to install their own flooring.
How Cork Flooring is Made
Cork is a renewable resource made from the bark of the cork oak tree (Quercus suber), an evergreen that grows in the Mediterranean region of Southern Europe and Northern Africa. These trees are grown specifically for the harvesting of their bark, which is done in the summer when the bark becomes loose from the tree's trunk. The harvesting process does not harm the trees, and the bark naturally grows back every 9 to 10 years, allowing a single crop of cork oaks to continue producing for decades.
Cork flooring is made with either slices or cork or granulated cork mixed with resin binders. There are two main types: solid-cork tiles are the traditional option and are designed for glue-down application. Cork planks are a laminated product made with a bottom layer of compressed cork, a core of medium-density or high-density fiberboard, and a top decorative layer of cork.
Planks typically have click-together edges for floating floor installations.
Benefits of Cork Flooring
Cork represents a unique blend of hard and soft flooring. It is a smooth, hygienic, easy-to-clean surface that's also easy on your feet and ears.
- Softness: If you have ever pulled a cork from a wine bottle, you know how soft and pliable this material can be. It has a yielding surface beneath the feet that is very comfortable to stand on, even for long periods of time.
- Quiet: Cork flooring is relatively quiet to walk on, much quieter than hardwood or laminate flooring.
- Renewable: Cork flooring is primarily made with wood products and is resource-efficient.
- Resilient: Cork’s ability to bounce back from impressions means that most objects will not leave dents in its surface.
- Non-slip: Even when wet cork can provide a good level of traction for your feet.
Drawbacks to Cork Flooring
Cork isn't the toughest flooring material, and it's vulnerable to moisture damage, so it must be protected from damage and excess moisture.
- Maintenance: Solid-cork tiles must be sealed with polyurethane or other protective finish after installation and every two to three years thereafter. Cork planks (floating floors) typically are sealed with polyurethane during manufacture but may need to be resealed periodically. All types of cork should be cleaned regularly to remove grit and dirt that can abrade the surface and lead to premature wear.
- Stains: If not sealed properly, cork can be stained very easily by dirt, spills, or other contaminants.
- Moisture: Cork flooring is generally not recommended in very moist environments unless it is properly sealed several times in order to protect the material. This seal will have to be reapplied periodically to prevent moisture from penetrating the surface of the floor.
- Dents: You will need to place protective mats underneath the legs of particularly heavy furniture to prevent permanent divots from forming.
Since cork is a natural material, the exact look of each piece will vary slightly, although in its natural unstained state it tends to be a pale tan or brownish color. Cork can come stained in a variety of hues, ranging from dark chocolate to pale honey. You can also get cork flooring stained green, blue, red, or virtually any color you desire.
Cork most commonly comes in tile form and is usually sold in standard 12-by-12-inch or 12-by-24-inch sizes. There are also cork planks that come in standard 12-by-36-inch boards.
In an application where you want there to be a minimum number of seams, cork flooring can be installed using sheet material. However, it represents a significantly more difficult and complicated installation process.
Standard residential cork flooring should be at least 3/16” in thickness. In a commercial application, you want at least a 5/16” thickness.
Cork Flooring Installation Tips
Specific installation methods and steps vary by flooring product, but most installations involve standard procedures. Always follow the manufacturer's installation specifications to prevent voiding the flooring warranty.
Tips for Cork Floating Floors:
- Install a high-quality foam underlayment over the subfloor before laying the finish flooring. Underlayment comes in different thicknesses for different levels of cushion and to set the flooring height level with flooring in other rooms.
- Let the flooring planks acclimate for several days in the room where the flooring will be installed.
- Provide an expansion gap of 1/4 to 1/2 inch (or as directed by the manufacturer) around the perimeter of the flooring installation, to allow the flooring to expand during humid weather.
- Install a manufacturer-approved moisture barrier over concrete basement floors, followed by a moisture-resistant underlayment below the flooring. Be sure that the flooring you use is approved for installation in basements and will be covered by the warranty.
Tips for Glue-Down Cork Tiles:
- Install cork tiles on a dry, smooth surface that has a maximum variance of plus or minus 1/8 inch. Generally, masonite or plywood is recommended for the underlayment. Tiles also can be glued directly to concrete if the floor is at or above grade (cork tiles are not recommended for basements).
- Do not install cork flooring over radiant floor heating systems, as they can cause the tiles to curl or the adhesive to become loose.
- Use a manufacturer recommended adhesive to install the tiles. In some cases, the cork will come with the adhesive already applied to its underside.
- Leave a 1/8- to 1/4-inch expansion space around the perimeter of the room to allow for shifts in size due to temperature and humidity changes.
- Weight down individual tiles as needed to ensure that you get a secure bond. Allow the floor to dry for 24 to 48 hours after installing it.
- Apply a protective finish, such as polyurethane, to the surface of the cork to protect the material and seal over the seams between the tiles. Pre-sealed cork may need only one or two coats to protect the seams, while untreated material will require several coats to create a protective layer over the material.