Standard Kitchen Cabinet Sizes and Hardware Compatibility Guide

When upgrading or building a kitchen, getting the hardware right depends entirely on understanding your carcass dimensions. Fitting high-performance drawer slides, concealed hinges, or wirework storage requires precise sizing; guessing can lead to misaligned doors, catching mechanisms, or fittings that simply do not fit inside the carcass. Familiarising yourself with standard kitchen cabinet measurements ensures every component operates smoothly and sits flush.

Carcase Widths and Internal Space

In the UK, modular kitchen units generally follow standard external widths based on metric increments. Typical base and wall units range from 150 mm for narrow pull-outs to 300 mm, 400 mm, 500 mm, 600 mm, 800 mm, 900 mm, 1000 mm, and 1200 mm. However, internal clear dimensions dictate hardware compatibility rather than external widths.

Most UK cabinet carcasses are built from either 15 mm or 18 mm MFC (melamine-faced chipboard), with 18 mm being the modern trade standard. When ordering wire larder pull-outs or internal corner carousels, always calculate the internal clear width:

• For an 18 mm carcass: Internal width = External width minus 36 mm (e.g. a 600 mm unit provides 564 mm internal width).
• For a 15 mm carcass: Internal width = External width minus 30 mm (e.g. a 600 mm unit provides 570 mm internal width).

Selecting Drawer Runners by Cabinet Depth

Standard base carcasses typically measure 560 mm to 570 mm in external depth, designed to sit under a 600 mm worktop once a service void (service gap behind the back panel) is factored in. Standard kitchen cabinets measurements directly determine the length of drawer runners you can fit.

Runner Length Selection

• 500 mm Runners: The industry standard for typical 560 mm deep base units. They maximise extension without fouling on the rear carcass panel.
• 450 mm Runners: Often chosen when a shallower unit is required or when deep pipework restricts the rear internal void.
• Side Clearance: Standard ball-bearing runners require exactly 12.7 mm (1/2 inch) clearance per side, meaning the drawer box must be built 25.4 mm narrower than the internal carcass width. Concealed undermount runners follow proprietary sizing charts based on drawer box side thickness (typically 13 mm to 16 mm).

Hinge Drilling Patterns and System 32

Modern cabinetry uses the standard System 32 drilling pattern, where line borings sit on 32 mm centres, precisely 37 mm back from the front edge of the carcass. When fitting concealed euro-style hinges, the door requires a 35 mm diameter cup hole drilled at a standard depth of 11.5 mm to 12.5 mm.

For full overlay doors on standard 18 mm sides, zero-crank (0 mm) hinge arms combined with standard 0 mm mounting plates allow the door to cover approximately 16 mm to 17 mm of the carcass edge, leaving a neat 1 mm to 2 mm gap between adjoining units.

Plinth Heights and Adjustable Legs

Base units typically sit on adjustable plastic plinth legs, lifting the bottom of the carcass off the floor to prevent water damage and provide space for a clip-on plinth panel. The standard UK plinth height is 150 mm, although modern contemporary kitchens frequently use 100 mm legs to allow taller carcasses and greater storage volume.

Frequently Asked Questions

What is the standard depth of a kitchen wall cabinet?

Wall carcasses generally have an external depth of 300 mm to 350 mm. Hardware fitted inside, such as lift-up flap stays or spice pull-outs, must be chosen according to this reduced depth compared to base units.

How do I know which hinge plate thickness to choose?

Hinge mounting plates are typically available in 0 mm, 2 mm, or 4 mm heights. For standard 18 mm carcass sides with full overlay doors, 0 mm plates are the standard choice. If your carcass sides are 15 mm or 16 mm, you may need a different plate height or hinge offset adjustment to achieve proper alignment.