Frequently asked questions

You have a question concerning the Cobra fastener products? Run through the list of frequently asked questions to find the answer. Should you not find the answer to your question, don't hesitate to contact us.


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About Cobra stainless steel 20 and 24 clips

  1. How long ago were the Cobra® clips developed?
  2. What are the advantages of the Cobra® clip?
  3. With what types of boards can the invisible Cobra® fasteners be used?
  4. How do I start installation with the first board?
  5. With what types of boards can the invisible Cobra® fasteners be used??
  6. What spread between boards is required by the clips?
  7. What is the maximum decking board width that can be used with Cobra® clips?
  8. Do the clips come with screws?
  9. How can I easily calculate the number of clips required per m²?
  10. How can I groove the boards to use the Cobra® clips?
  11. What is the average installation time with Cobra® clips?
  12. How does one go about replacing a defective board?
  13. How do I install a "banana" board?
  14. Are Cobra® clips really invisible?
  15. Why must the space between the boards be at least 5mm?
  16. What is the Cobra® clips guarantee?
  17. How are the Cobra® clips manufactured?
  18. What is the metal used in the manufacture of the Cobra® clips?
  19. What is a wood decking board's maximum moisture content for installation with Cobra® clips?
  20. What's the purpose of the claws on the clip?

  1. How long ago were the Cobra® clips developed?

    The black lacquered stainless steel clips were designed over 10 years ago by a team of engineers. The product was developed in partnership with decking installers and manufacturers with the goal of meeting all installation constraints and providing an attractive and dependable fastening system.

  2. What are the advantages of the Cobra® clip?

    The Cobra® clip is a convergence of advantages: an invisible fastening system (black matte and fastening between boards), practicable removable, and quick to install. It is made in A2 stainless steel (304 stainless steel) to meet the demands for outside use.

  3. With what types of boards can the invisible Cobra® fasteners be used?

    The Cobra® clip can be used on composite, thermally modified wood and kiln dried exotic wood (KD 14-18%) decking boards. The board chamfer must be greater than 4mm. For decking boards in natural wood, the width must not exceed 140mm.

  4. How do I start installation with the first board?

    The first and last boards must be fastened to the sleeper with start and end clips: Cobra Start/End Clip. For composite wood decking boards, you can also use the Cobra® WPC screw in the same color as the board (size 5x50mm or 5x63mm).

  5. With what types of boards can the invisible Cobra® fasteners be used?

    Click here to view the board profiles that are compatible with the Cobra fastening system

  6. What spread between boards is required by the clips?

    Between dry periods (summer or dry season) and wet periods (winter and rainy season), wood is subject to swelling and shrinkage. Taking this into account, the Cobra® clip calls for a regulatory spacing of 6mm (+/-1mm) between the boards.

  7. What is the maximum decking board width that can be used with Cobra® clips?

    There is no limit for composite and thermally modified wood boards however for natural wood, the width of the decking board cannot be greater than 140mm. In all other cases, the slenderness coefficient of the board (width/thickness) must meet the standard required by DTU 51.4.

  8. Do the clips come with screws?

    The Cobra® clips come in thermo-sealed bags. Each bag contains 90 Cobra® clips + 90 screws + 1 end cap.

  9. How can I easily calculate the number of clips required per m²?

    The number of clips per m² depends on two parameters: the distance between the sleepers and the board width.
    As a general rule, the number is equal to [1/(distance x width)]x1.05. Note the values must be indicated in meters (m).

  10. How can I groove the boards to use the Cobra® clips?

    The Cobra® clip can only be used on a board that is properly grooved and profiled. Two options are possible:

    • 1st case – You received the boards at the work site and they are not grooved: the grooves on the board edge can be made with a simple groove cutter (Lamello type) according to the instructions supplied by the manufacturer. In this situation, the groove is made locally at the junction between the board and the sleeper.
    • 2nd case – the boards are still at your wood merchant's: have the boards pre-grooved along the length of the boards, in the finishing workshop or even directly at the wood merchant's.

    In both cases, be sure to respect the height and depth of the groove. Click here to view the dimensions to respect.

  11. What is the average installation time with Cobra® clips?

    The Cobra® clip reduces decking installation time by 30% compared to a screwed down installation. With its self-drilling screw, only a simple bit (supplied) is required to attach the Cobra® clip to the sleeper (see assembly video).

  12. How does one go about replacing a defective board?

    The Cobra® clip allows for the junction between two boards placed end to end. This allows for the replacement of a damaged side without having to remove installed decking.
    Click here for the installation manual.

  13. How do I install a "banana" board?

    The camber phenomenon can appear :

    • On natural wood boards: if the board was improperly dried, or if the board was poorly stocked or subjected to sudden variations in temperature.
    • On composite wood boards: this is a common problem especially on long boards.

    In this case, the Cobra Wrench® can straighten twisted or distorted decking boards with its system of lugs that attach to the sleepers and are adaptable to all sections.

    The misshapen boards are immediately straightened and are ready to be fastened, with both hands free. Reversible, it can be used in the right hand as well as the left hand so as to be operational in all situations.

    Click here to see the video.

  14. Are Cobra® clips really invisible?

    The Cobra® clips are made in A2 stainless steel, in a black matte color (to avoid reflections off the stainless steel) and are much less visible than other clips on the market.

  15. Why must the space between the boards be at least 5mm?

    Between dry periods (summer or dry season) and wet periods (winter and rainy season), wood is subject to swelling and shrinkage. Taking this into account, and according to DTU 51.4 which defines the rules for implementation of outside wood decking platforms, the placement of the boards over the entire life of the structure must respect the following rule:
    spacing never less than 3mm or greater than 12mm on standard lengths up to 140mm approximately.

    We recommend leaving a 5 to 6mm play between the boards to better ventilate the structure and to allow for the removal of organic wastes and other bits of dirt that could block the play between the boards.

  16. What is the Cobra® clips guarantee?

    The Cobra® clip is guaranteed against breakage for:

    • A maximum tensile (pull-out) force of 2.5 dN (or approximately 250kg)
    • A maximum shearing force of 6.5 dN (or approximately 650kg)
  17. How are the Cobra® clips manufactured?

    The Cobra® clips are made from A2 stainless steel sheets which are embossed and then vaporized with a black matte paint.

  18. What is the metal used in the manufacture of the Cobra® clips?

    The Cobra® clips are made from A2 stainless steel (304 stainless steel) and so are compatible with outside use.
    Note that superficial rust spots can appear on A2 stainless steel if the surrounding atmosphere is polluted (industrial, port, or chemical industry areas) or if the decking is located in a marine environment or near the ocean.

  19. What is a wood decking board's maximum moisture content for installation with Cobra® clips?

    The wood decking boards must be KD (kiln dried) 14-18%.

  20. What's the purpose of the claws on the clip?

    The claws are located on the clip flanges to hold the board firmly in place on the sleeper. They reduce distortions to certain boards that can twist as a result of temperature differences and ambient moisture.
    They can also correct a cambered ("banana" effect) board.