Glass Door Hinges for Display Cabinets: Concealed Hinges for Glass Fronts (26mm / 35mm)

March 17, 2026

A glass door hinge connects a glass front securely to the cabinet carcass and, unlike wooden door hinges, requires specialised fixing methods such as a drilled hole in the glass or a gentle clamping technique.

When constructing display cabinets, mirror cabinets, or modern living room furniture, glass presents fitters with specific mechanical challenges. The material is brittle, heavy, and unforgiving of stress peaks during installation. Standard concealed hinges / cabinet hinges for timber-based materials cannot be applied directly to glass, as woodscrews are entirely ineffective. Instead, a modified concealed hinge is used, where the cup passes through a precision hole in the glass and is clamped or screwed from the outside using a decorative cover cap.

This guide takes you through the technical specifications, selection criteria, and proper installation of glass door hinges in detail.

Types and Styles of Glass Door Hinges

Choosing the right hinge for a glass front depends primarily on the method of attachment to the glass, the drilling diameter, and the door position relative to the carcass.

Concealed Hinges for Glass Fronts (Drilled)

The sturdiest and most widely used method in professional cabinet making is the drilled concealed cup hinge. A hole is drilled into the glass pane, through which the hinge cup is inserted. On the outside of the door, a cover cap (usually made of plastic or zamak) is positioned and screwed into the cup on the inside. The glass is firmly clamped between the cup and the cap. Plastic spacer rings prevent direct contact between metal and glass.

Two standard drilling diameters have become established:

26 mm cup drilling: The standard for most display cabinets and lightweight glass fronts. These hinges are compact and cause minimal disruption to the look of the transparent door.
35 mm cup drilling: Used for very large, heavy glass doors. A 35 mm concealed hinge for glass offers a larger contact surface and distributes the clamping pressure better across the sensitive material.

Clamping Hinges (Non-Drilled)

For smaller, lightweight glass doors (such as in compact Hi-Fi units), clamping hinges are available. These do not require any drilling in the glass. The pane is simply inserted into a U-profile on the hinge and secured via a clamping screw (with a plastic or rubber pad). However, this variant carries significantly less weight and is unsuitable for large display cabinet fronts.

Door Overlay Types for Glass Fronts

As with timber doors, the overlay type defines how the glass door sits against the carcass edges when closed. This must be considered during hinge planning:

Full overlay: When closed, the glass door rests almost entirely over the carcass edge. From the front, the carcass side edge is barely visible, if at all. A full overlay concealed hinge is required for this setup. The hinge arm crank value is typically 0 mm.
Half overlay (twin overlay): When two glass doors share a single central carcass divider, they cannot cover the full width of the edge without colliding. A half overlay hinge features a cranked arm (usually 9.5 mm) so that each door covers only half the edge thickness.
Inset: The glass door sits flush with the outer carcass edges, positioned fully inside the cabinet frame. The hinge arm is heavily cranked (usually 16 mm or more).

Buying Criteria: How to Choose the Right Concealed Hinge for Glass

The hinge specification must match the physical characteristics of the glass door and its required function precisely.

Glass Thickness and Weight

Standard glass door hinges are engineered for glass thicknesses of 4 mm - 6 mm. The spacer rings and the length of the cover cap fixing screws are standardised specifically to this dimension. If the glass is thinner, the clamp will not grip sufficiently; if it is thicker, the cap and cup cannot be screwed together.

The weight of the door dictates the number of hinges required. Glass is heavy. The rule of thumb for calculation: one square metre of glass at 1 mm thickness weighs exactly 2.5 kg. A display cabinet door measuring 1000 mm x 500 mm with a thickness of 4 mm therefore weighs exactly 5 kg (0.5 m² × 4 × 2.5).

Up to 5 kg and 900 mm height: 2 hinges.
Up to 9 kg and 1600 mm height: 3 hinges.
Up to 12 kg and 2000 mm height: 4 hinges.

Opening Angle

The opening angle determines how easily the cabinet interior can be accessed.

95° / 110°: The standard for classic display cabinets. A 110-degree concealed / cabinet hinge provides comfortable access without projecting too far into the room.
155° / 165°: Wide-angle hinges are used less frequently on glass fronts, but are necessary when internal drawers behind the glass door need to be pulled out.

Damping and Opening Mechanisms

Modern furniture fittings offer high convenience, which should not be missed on glass fronts.

Soft-Close: A hinge with integrated damping brakes the glass door over the final centimetres of its closing travel and pulls it gently and silently against the carcass. A soft-close concealed / cabinet hinge prevents the heavy glass pane from slamming against the carcass edge, which could otherwise lead to glass breakage.
Push-to-Open (Tip-On): For entirely handleless display cabinets, unsprung hinges (without spring retention) are used in combination with a touch latch. Pushing the glass releases the door to spring open. Note: Soft-close and push-to-open are opposing mechanisms and cannot be combined within the same hinge.

Applications in Cabinet Making

Glass door hinges are specialised components that meet varying demands across different rooms. The hinge acts as the discreet backbone of the display unit: it supports the weight of the heavy pane while visually taking a back seat to the transparency of the furniture.

Living and Dining Rooms

In collector display cabinets or illuminated highboards, aesthetics take centre stage. Hinges with a 26 mm cup drilling are most commonly chosen. The visible cover caps on the outside can be colour-matched to the cabinet style – polished chrome, brushed stainless steel, or matt black are popular options. These doors are frequently secured with a display cabinet lock to protect valuable collections. Internally, glass shelf supports are used alongside them to provide non-slip support for glass shelving.

Bathrooms (Mirror Cabinets)

Mirror cabinets often use doors where a mirror is bonded over a backing panel. However, if the doors consist purely of mirrored glass, glass door hinges are also required. High corrosion resistance of the metal components is essential here due to the elevated humidity levels in bathrooms.

Kitchen Wall Units

Kitchens often feature frosted or reeded glass panes within aluminium frames. Please note: aluminium frame doors require dedicated aluminium frame hinges, not glass hinges. However, if the front consists entirely of glass, models with a sturdy cruciform mounting plate and integrated damping are essential due to frequent daily use.

Installation and Technique: Fitting Glass Fronts Securely

Installing a glass door hinge demands precision. While a DIYer working with chipboard can conceal minor drilling mistakes with filler, a hole drilled in glass is permanent.

Required Tools

Cordless drill/driver
Glass drill bit / diamond core drill bit (26 mm or 35 mm)
Pozi or Phillips screwdriver (PZ or PH drive)
Rule and try square
Water spray bottle (for cooling during drilling)

Step-by-Step Installation

Drilling the glass: If the door is not pre-drilled from the factory, the hole must be cut. The glass must rest completely flat on a soft, supporting surface. Drill without hammer action using a diamond core bit. The drilling site must be constantly cooled with water to prevent thermal stress fractures. The distance from the glass edge to the hole (cup distance) is typically between 3 mm - 7 mm, depending on the hinge manufacturer.
Inserting the cup: Open the hinge. Place the plastic spacer ring into the drilled hole. Then feed the hinge cup through the glass from the inside.
Securing the cover cap: Place the second plastic pad onto the outer face, followed by the decorative cover cap. Drive the screws from the inside through the hinge cup into the cap. Important: Tighten by hand only. Overtightening screws creates internal tension that can crack the glass.
Fitting the mounting plate: Screw the cruciform mounting plate to the inside of the carcass following the System 32 grid. Chipboard screws with a diameter of 3.5 mm or 4 mm are generally used here.
Hanging the door: On modern hinges with clip-on mounting, simply press the hinge arm onto the mounting plate until it audibly clicks into place.

3D Hinge Adjustment

Once hung, a glass door is rarely aligned perfectly straight away. The adjustment screws on the hinge arm allow the gaps to be fine-tuned precisely:

Depth adjustment: An eccentric screw at the rear of the hinge arm alters the gap between the glass and the carcass (typically +2 mm / -2 mm).
Side adjustment: The front screw on the arm moves the door left or right, regulating the reveal between adjacent doors.
Height adjustment: Loosening the fixing screws on the cruciform mounting plate allows the entire door to be moved vertically by several millimetres.

Frequently Asked Questions (FAQ)

What hole diameter is standard for glass door hinges? The standard diameter for glass concealed hinges is 26 mm. For particularly heavy or large glass doors, 35 mm versions are also available to distribute the load more effectively.

Can I install a concealed hinge on glass without drilling? No, a true concealed cup hinge always requires a hole drilled through the glass to house the cup. If drilling is not an option, clamping hinges must be used instead, though they offer a significantly lower load capacity.

What is the difference between full overlay and inset for display cabinets? With full overlay, the closed glass door sits over the carcass side walls, concealing the carcass edges from the front. With an inset concealed hinge, the door sits flush between the carcass side panels, leaving the front edges of the cabinet sides visible on either side of the glass.

How do I adjust a glass door hinge correctly? Adjustment is carried out using the three screws on the hinge arm (3D adjustment). The front screw regulates the lateral reveal, the rear eccentric screw adjusts the depth distance between door and carcass, and the mounting plate screws adjust the vertical height.

How much weight can a glass door hinge support? A standard glass door hinge generally supports between 2.5 kg and 3.5 kg. A typical display cabinet door weighing 5 kg requires at least two hinges. For doors weighing 9 kg or more, three hinges should be fitted.

Do I need special cover caps for the glass? Yes. Because the hole passes right through the glass, the metal hinge cup would otherwise be visible from the outside. Glass door hinges are therefore always supplied with matching cover caps (round, semi-circular, or oval) that screw on from the outside and serve as the clamping counter-piece.

Can I retrofit soft-close onto glass doors? If the existing hinges do not have integrated damping, soft-close cannot usually be added directly to the hinge itself. Alternatively, separate clip-on dampers (if available from the manufacturer for that specific series) or simple drill-in buffer dampers installed in the carcass can be used to cushion the glass door.

Related Categories & Guides

To complete your furniture project successfully, explore our range of specialised fittings and hardware designed to work seamlessly with glass fronts. If you are building standard wooden cabinetry alongside display units, take a look at our core hardware ranges.