Types of Wood Joints
The main types of wood joints are the butt, miter, rabbet, dado, groove, tongue and groove, dowel, biscuit, pocket hole, half lap, box, mortise and tenon and dovetail joints, plus screwed connectors for flat-pack furniture. Which one to use depends on the material and the load: solid wood suits interlocking joints like the mortise and tenon, while plywood, MDF and particle board work best with dadoes, rabbets and screws or dowels. Together they make up the joinery of most furniture. For flat-pack fittings, see cam locks and confirmat screws.
Wood joints at a glance
| Joint | Strength | Tools | Best for |
|---|---|---|---|
| Butt joint | Weak alone, good with screws | Saw, drill | Quick boxes, hidden frames |
| Miter joint | Weak alone, good with splines | Miter saw | Frames, edges where end grain must not show |
| Rabbet | Good | Table saw or router | Cabinet backs, box corners, drawer fronts |
| Dado | Very good | Dado blade or router | Shelves and bottoms in cabinets and bookcases |
| Groove | Good | Table saw or router | Drawer bottoms, panels in frames |
| Tongue and groove | Good | Router or shaper | Joining boards edge to edge, panels |
| Dowel joint | Good | Drill, dowel jig | Plywood, MDF and particle board carcasses |
| Biscuit joint | Medium (alignment) | Biscuit joiner | Aligning panels and edge joints |
| Pocket hole | Good | Pocket hole jig | Face frames, carcasses, quick furniture |
| Confirmat screw | Very good in boards | Step drill | Melamine and MDF cabinets |
| Half lap | Good | Saw or router | Frames, crossing rails |
| Box (finger) joint | Very good | Table saw jig or router | Boxes and drawers |
| Mortise and tenon | Excellent | Chisel, router or mortiser | Tables, chairs, doors |
| Dovetail | Excellent | Saw and chisel, or jig | Drawers and fine boxes |
Joints for sheet goods
Plywood, MDF and particle board are flat, stable and come in big panels, so cabinet joints are simple and rely on glue surface and fasteners:
- Butt joint with screws: the fastest. In plywood, pre-drill and glue; in MDF and particle board, use confirmat screws instead of wood screws.
- Dado: a channel across the panel that the shelf or bottom sits in. It carries the weight even if the glue fails. See dado and rabbet joints.
- Rabbet: a step along an edge, for backs and box corners.
- Dowels: 8 mm (5/16 in) dowels with glue, every 100–150 mm. The standard knock-down-free joint in European cabinets.
- Pocket screws: angled screws driven from the hidden face; very quick and strong enough for most cabinets. See how to use a pocket hole jig.
- Cam locks and connectors: for furniture that must come apart.
Joints for solid wood
Solid wood moves with the seasons and has strong long grain, so its joints interlock: mortise and tenon for tables and doors, dovetails and box joints for drawers and boxes, half laps for frames, and tongue and groove or glued edge joints to make wide panels. End grain glues poorly, which is why these joints turn end grain into long-grain glue surfaces.
Choosing a joint
- Will it be seen? Hide fasteners on the inside or under edge banding; show off dovetails and box joints.
- What carries the load? A shelf in a dado cannot drop even if the glue fails; a shelf on pins can be moved.
- What tools do you have? With a drill and a saw: screws, pocket holes and dowels. With a router or a table saw: dadoes, rabbets and grooves.
- Will it come apart? Use connectors for anything that must be moved through a narrow door.
Our plans tell you which joint each part uses and size the parts for it, so a shelf that goes into a dado comes out the right length:
Frequently asked questions
What is the strongest wood joint?
For solid wood, the mortise and tenon and the dovetail, because they lock the parts mechanically and give a large glue surface. For plywood and MDF, a glued dado or a rabbet reinforced with screws.
What is the easiest wood joint?
The butt joint: two square ends glued and screwed together. Pocket screws or dowels make it much stronger with very little extra work.
Which joints are best for plywood?
Dadoes and rabbets glued and nailed or screwed, pocket screws, dowels, biscuits and confirmat screws. Joints cut into end grain, like dovetails, are weak in plywood because of its layers.
Which joints work in MDF and particle board?
Confirmat screws, dowels with glue, cam-lock fittings and dadoes. Ordinary wood screws driven into the edge of MDF or particle board tend to split it or pull out.