CORK UNDERLAYMENT INSTALLATION INSTRUCTIONS
- Specification Data on Product #8244
- Green Building Ratings
- General Installation Instructions
- Installation Instructions – Tile Floor over Radiant Heat on Concrete Slab
- Sound Control for Hard Surface Flooring Applications
Cork is a natural material, extremely effective for sound control (independently tested according to ASTM standards for acoustical values) and is an effective thermal insulation barrier. In addition, cork offers important stress crack protection.
Quite easy to install, environmentally friendly, cork underlayment does not deteriorate after years of use and is an ideal and economical solution for your underlayment requirements. Specification Data on Product #8244 is available on request.
Please read installation instructions completely before installing cork underlayment.
The preferred underlayment panel is APA underlayment grade plywood, minimum thickness of 1/4″, with a fully sanded face. Note: Particleboard, chip board, Masonite, and lauan are not considered the most suitable underlayments.
Surface must be clean, dry and smooth, free of voids, projections, loose materials, oil, grease, sealers and other surface contaminants. Maximum floor variation is 1/8″ in 10 feet. Surface areas requiring patching or leveling should be be repaired with Portland based-cement materials.
Creating and Isolation Barrier:
Unroll cork and cut sections approximately 2″ wide off roll. Adhere this 2″ isolation barrier around all perimeter walls and around any protrusions through the flooring, such as beams, plumbing, etc., with any of the following products:
Natural Rubber Latex Adhesives
Cartridge Filled Urethane
Acrylic Bead Mastics
Never mechanically flatten the isolation barrier with screws, nails, or staples. This will severely diminish acoustical values of the barrier.
Installing Cork Underlayment:
- Unroll cork and cut to desired length. Lay cork loosely over area to be installed. Both ends of the roll must curl down towards the subfloor. If the ends curl up, flip material over. Butt cork directly against the isolation barrier already installed.
- Pull the loose laid material back at least half the length of the roll.
- Using a 3/16″ x 5/32″ v-notch trowel, apply any of the Bostik products listed above to the subfloor. Gently return the pulled back material and roll in both directions with a 100-lb roller. Repeat this procedure for the other half of the roll. Proceed to cover the entire floor making sure all joints are butted together tightly. Note: If BossTack adhesive is used, allow to flash until dry, the apply cork and roll with 100 lb. roller (refer to BossTack data sheet).
- Allow cork adhesive to take a firm set prior to installing hardwood or ceramic tile flooring. Read adhesive manufacturers instructions to determine adhesive set time.
Wood Flooring Installation: Apply to cork as follows:
- Follow industry standards and wood floor manufacturer recommendations for subfloor moisture content, design, layout and application of wood flooring materials.
- Refer to Bostik’s Best, BST Urethane, or BossTack adhesive data sheets for full wood flooring installation instructions.
- When the flooring installation is complete, trim the sound isolation barrier so that it is flush with the floor.
- Seal the gap between the flooring and the walls or other protrusions with Acoustical Caulk.
- Natural Cork underlayment is available in rolls 4′ x 50′ x 6mm (ships via UPS), 4′ x 100′ x 6mm, 4′ x 200′ x 3mm thickness. Cork rolls can be easily sheeted with a sharp knife or razor blade.
Ceramic Tile Flooring Installation: Apply to cork as follows:
Install ceramic tile according to applicable ANS. Standards using Hydroment SingleOFlex; Hydroment PM; or Tile-Mate Thin Set Mortars mixed with #425 Multi-Purpose Acrylic Latex Admixture or #447 Flex-a-lastic Admixture.
Refer to setting mortars data sheets for complete instructions.
When the flooring installation is complete, trim the sound isolation barrier so that it is flush with the floor.
Seal the gap between the flooring and the walls or other protrusions with Acoustical Caulk.