Inset vs Overlay Hinges: Which Do You Need?

When planning a kitchen renovation, building bespoke cabinetry, or replacing worn-out hardware, selecting the correct concealed hinge is essential. One of the most common dilemmas faced by DIY enthusiasts and joiners alike revolves around inset vs overlay hinges. While these fittings often share identical 35 mm cup drillings, their geometry is engineered for entirely different door configurations. Choosing the wrong type can prevent your doors from closing properly or leave unsightly gaps. Here is everything you need to know to get the right fit every time.

Understanding Cabinet Door Positioning

Before looking at hinge mechanics, you must assess how the cabinet door sits in relation to the carcass (the cabinet frame or box). In modern cabinetry, there are three primary door positions:

• Full Overlay: The door sits entirely over the front edge of the cabinet carcass, concealing the side panel almost completely when closed.
• Half Overlay (Twin): Two adjacent doors share a single central divider panel (usually 18 mm thick). Each door covers roughly half of the carcass edge.
• Inset (In-frame / Embedded): The door sits flush inside the cabinet opening, surrounded completely by the carcass frame.

The Core Differences: Inset vs Overlay Hinges

The distinction between an inset hinge vs overlay hinge lies in the 'crank' or bend of the hinge arm. The crank determines how far the door projects outwards and sideways when opened, as well as where it rests when closed.

Full Overlay Hinges Explained

Full overlay hinges are the most widely used fittings in modern flat-pack and modular kitchen units. Featuring a straight hinge arm, they position the door so that it sits over the front edge of the carcass, leaving only a tiny margin (typically 1 to 2 mm) for clearance. This creates a clean, streamlined appearance where minimal cabinet framework is visible between units.

Half Overlay Hinges Explained

Half overlay fittings, sometimes called twin hinges, are designed for units where two doors meet on a single central upright. Because both doors must mount onto the same 18 mm board, a standard straight-arm hinge would cause the doors to collide. The half overlay hinge arm features a gentle bend that offsets the door, allowing each door to overlay approximately half the board's thickness (around 8 to 9 mm) without interference.

Inset Hinges Explained

When considering overlay vs inset hinges, inset configurations require the most precision. The hinge arm has a pronounced, deep crank that holds the door inside the cabinet box rather than over the front edge. When closed, the outer surface of the door is completely flush with the front edges of the carcass. Inset doors require careful alignment to ensure consistent perimeter reveals (normally 2 to 3 mm all the way round) so the door can swing freely without catching against the frame.

How to Measure and Choose Correctly

If you are replacing existing fittings or building from scratch, follow these practical steps to determine the hinge type you need:

1. Inspect the closed door: Look at where the door edge sits. Does it cover the front edge of the cabinet side, or does it sit inside the frame opening?
2. Check shared panels: If the door covers the panel, check if another door is mounted to the opposite side of the same divider. If yes, you need a half overlay hinge. If it is an independent end panel, you need a full overlay hinge.
3. Check mounting plates and cup depth: Standard European concealed hinges use a 35 mm diameter cup hole drilled into the back of the door, typically 11.5 mm to 12.5 mm deep. Ensure your existing door preparation matches standard trade dimensions.

Frequently Asked Questions

Can I turn an overlay cabinet into an inset cabinet using new hinges?

Not simply by changing the hinges. Inset doors must be smaller than overlay doors because they have to fit completely inside the internal dimensions of the cabinet carcass with clearance gaps around the perimeter.

Are mounting plates interchangeable between inset and overlay hinges?

In most standard 32 mm system fittings, the mounting plates (which screw onto the carcass wall) share the same fixing patterns. However, the height of the mounting plate (e.g. 0 mm, 2 mm, or 4 mm) interacts with the hinge crank to determine the final door overlay or reveal.