What Are Interior Hinges: A Comprehensive Guide to Hidden Door Hardware

What are interior hinges? Interior hinges, commonly referred to as concealed hinges or European hinges, are a type of hardware used for hanging doors on cabinets and furniture where the hinge mechanism is not visible from the outside when the door is closed. Unlike traditional visible hinges, these are mounted on the inside of the cabinet door and the frame, creating a clean, seamless aesthetic. The most prevalent type is the cup-and-arm hinge system, which involves a hinge cup drilled into the door and a mounting plate attached to the cabinet carcass. This design is the industry standard for modern kitchen cabinets, wardrobes, and various built-in furniture due to its adjustable nature and minimalist appearance. The core principle is to hide the functional components, leaving only the clean lines of the furniture visible, which aligns with contemporary and minimalist design trends. Their invention and widespread adoption revolutionized cabinet making, moving away from the decorative, visible hinges of the past towards a focus on uninterrupted surfaces and functional hardware.

The functionality of interior hinges is rooted in their specific design and engineering. The primary component is the hinge cup, typically 35mm in diameter, which is drilled into the back of the door. This cup houses the mechanism that connects to the hinge arm, which in turn is fastened to a mounting plate on the cabinet's interior. A key feature that sets them apart is their multi-dimensional adjustability. Using a screwdriver, installers can typically make three types of adjustments: height (up and down), depth (in and out), and side-to-side (left and right). This allows for perfect alignment of doors after installation, compensating for any slight imperfections in the cabinet carcase or the door itself. The range of motion, or opening angle, is another critical aspect. Standard interior hinges often open to 95-110 degrees, but many are available with 165-degree or even 170-degree opening angles, providing wider access to the cabinet's interior, which is particularly useful for corner cabinets. Furthermore, they are designed to work with specific overlay measurements—the amount the door covers the cabinet frame. Options include full overlay (covering almost the entire frame), partial overlay (covering part of the frame, used on face-frame cabinets), and inset (where the door sits flush within the frame). The development of soft-close mechanisms, which are often integrated directly into the hinge, has become a standard expectation, preventing doors from slamming shut and enhancing the user experience. This complex system of cups, arms, plates, and screws, while hidden from view, is precisely engineered to provide reliable, long-lasting, and user-friendly operation for daily use.

Advantages of Interior Hinges