Learning Center

Find the answers to your home improvement questions.

How to Prepare a Subfloor for Glue Down Cork Flooring


When it comes to glue down cork flooring, it is necessary to have a subfloor that is free of dirt, debris, grease, and anything else that could prevent a good bond. Before you prepare your subfloor, you need to know what type of subfloor you’ll be installing on top of. Here are commonly used types of subfloors:

  • Concrete
  • Cement floor screed
  • Anhydrite or plaster screeds
  • Mastic asphalt
  • Chipboard and plywood with tongue-and-groove joints
  • Ceramic or natural stone tile floors
  • Screeds with underfloor heating

To achieve a lasting bond between the subfloor and cork floor, a properly prepared subfloor must have the following elements:

  • The subfloor must be structurally sound.
  • The subfloor must be clean. The surface, therefore, must be free of oil, grease, wax, dirt, asphalt, curing compounds, latex and gypsum compounds, dust, paint, or any contaminant, which may hinder a good bond. For existing wood floors, use a paint or varnish remover, and then scrub with tri-sodium phosphate. In case of tough stains, paint, or hard residues, you may have to machine sand the floor. Once this procedure is done, the floor must be washed, rinsed, and allowed to dry.
  • The subfloor must be level and flat to 3/16″ per 10-feet radius. Additionally, the subfloor should be smooth and free of all bumps and imperfections. If the subfloor is uneven at any point, it will definitely show on the surface of the cork floor. Existing wood floors must be leveled and all cracks should be filled with wood filler or finished plywood. In some cases, existing floors can be covered with 3/8″ plywood. Make sure the plywood has both its sides finished and is secured firmly. This will help you make sure the subfloor is even. Later, make sure to vacuum the room.
  • The subfloor must be protected from moisture.
  • Cork tiles can be installed directly over concrete subfloors. But make sure the concrete is smooth and dry. Concrete floors (either new or existing) must be leveled with latex fill. Also, prime it with the standard concrete primer. The floor can also be sanded later to ensure uniformity.
  • Concrete must be fully cured, for at least 60 days. If the concrete slab is not level, grind down high spots and fill low spots with leveling compound. Do not install on concrete unless you are sure it is not prone to moisture seepage.
  • The moisture content of a wood subfloor must not exceed 12%, while concrete moisture content must not exceed 3 lbs.
  • Wood subfloors must be dry and well secured. Nail or screw every 6″ along joists to avoid squeaking. If they’re not level, sand down high spots and fill low spots with an underlayment patch.
  • If you are installing cork flooring on existing vinyl or other smooth surfaces, ensure the adhesive bonds the two surfaces strongly. If you’re unsure, seek advice from a professional as to what products to use in your given situation, and always read the labels of the products you buy. Always follow the instructions carefully.
  • Cork floors are not recommended to be installed at below grade locations unless necessary precautions are taken to prevent moisture penetration through the subfloor. It is often necessary to ensure that an efficient moisture barrier is installed.
Have you prepared a subfloor before?

Looking for the right cork floor to install? Click here to take a look at our online selection of genuine Portuguese cork flooring.

(2) Comments

  1. Hello,
    I have a wood floor. I was going to do a vapor barrier then Hardi-backer sub floor. My main question is I was thinking about gluing down a 1/4 inch cork sub floor wondering if the cork tiles would glue down to the cork sub floor with no problem. I have some saples from you. Are they the thickness the original tiles are also?
    Jerry Fowler
    239 229 7983

    • BuildDirect Product Expert Team
      BuildDirect Product Expert Team - Reply

      Hi Jerry,

      Thank you for getting in touch! I would not recommend gluing down the cork tiles on top of a cork subfloor. You will have a lot of issues with both the flooring and the underlay. If you are gluing down cork it will need to be on a plywood or concrete subfloor. Also, the sample thickness will be the same as the actual tiles, they are just cut up pieces of the actual product. Please let us know if you have any other questions!

Leave a Reply

Your email address will not be published. Required fields are marked *

You can use these HTML tags and attributes <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>

Notify me of followup comments via e-mail. You can also subscribe without commenting.