Understanding Tongue and Groove
Tongue and Groove (T&G) refers to a common method of joining two flat pieces, typically wood, edge to edge. Each piece is profiled with a protruding ridge (the tongue) on one edge and a recessed slot (the groove) on the opposite edge.
How it Works:
The tongue of one board is designed to fit snugly into the groove of an adjacent board. This interlocking mechanism offers several advantages:

- Strong Interlock: Creates a robust mechanical joint between pieces.
- Alignment: Ensures boards are accurately aligned, resulting in a flat and even surface.
- Stability: Reduces individual board movement, warping, or cupping.
- Gap Prevention: Minimizes spaces between boards, especially useful for flooring and paneling where seasonal changes can cause material to expand or contract.
- Concealed Fastening: Often allows for "blind nailing" where fasteners are driven through the tongue and subsequently hidden by the groove of the next board, providing a clean look.
Common Applications:
Tongue and groove joinery is extensively used in:
- Wood flooring (hardwood and engineered)
- Wall and ceiling paneling (e.g., beadboard, shiplap variations)
- Exterior siding
- Subflooring and roof decking
- Cabinet construction and furniture making
This system provides a durable, aesthetically pleasing, and stable connection for various construction and woodworking projects.