What is a hardwood flooring spline, and how does it work?

Posted: November 13, 2023

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A hardwood flooring spline is a thin strip of wood, typically made from the same type of wood as the flooring itself. It is used to bridge the gap between two pieces of flooring where they meet at a joint. Hardwood flooring splines are commonly used when you need to change the direction you are laying your wood floor. The change in direction can occur for various reasons, such as transitioning from one room to another, creating a design pattern, or accommodating structural features in the space. Here’s how a hardwood flooring spline is used in such scenarios:

  1. Transitioning Between Rooms: When transitioning from one room to another with hardwood flooring, you may need to change the direction of the flooring planks to align with the new space. If you have a hallway or doorway where the planks need to run perpendicular to the existing flooring, you will often use a hardwood flooring spline.
  2. Preparing the Subfloor: Before making the directional change, ensure the subfloor is properly prepared. Make sure it’s clean, level, and free of debris. You may need to install an underlayment, especially in areas with significant subfloor height variations.
  3. Cutting the Groove: To change the direction of the planks, one row of planks will need to have a groove cut into the side where the direction will change. This groove will accommodate the hardwood flooring spline. The planks in the new direction will have a corresponding tongue on them.
  4. Inserting the Spline: Place the spline into the groove you cut in the row of planks. Ensure it fits snugly and is aligned with the existing tongue and groove system of the flooring.
  5. Gluing and Securing: Apply wood glue or adhesive to both the groove in the first row of planks and the spline itself. Then, slide the planks with the tongues into the hardwood flooring spline. Use clamps or weights to keep everything tightly connected while the adhesive dries. This creates a secure “locked-in” joint.
  6. Continue Installation: With the spline in place, you can continue installing the hardwood flooring in the new direction, making sure to engage the tongues and grooves as you move along.
  7. Maintain Aesthetics: The use of a spline helps maintain the visual continuity of the flooring even when changing direction, resulting in a professional and seamless appearance.

Changing the direction of your hardwood flooring using a spline is a common practice and allows for greater design flexibility. It’s important to take your time, measure accurately, and use proper installation techniques to ensure a smooth and even transition between the different directions of the flooring. Proper installation techniques and quality adhesive are key to the long-term stability and durability of the flooring.

Our knowledgeable and educated staff is here to answer any additional questions you may have about our sustainable wood flooring and more. Please call us today for a free quote: Ph# 406.642.7120 or click here to submit an inquiry online. We look forward to working with you on your next project!



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