Replacement Drawers for IKEA Pax Wardrobes

A retrofitted drawer system for wardrobes uses the standardised System 32 hole spacing to integrate precisely into existing carcases via 5 mm drilling lines.

Introduction: Expanding the Functionality of Wardrobe Carcases

When planning storage space in bedrooms or dressing rooms, the wardrobe carcase forms the structural framework. Over time, however, internal layout requirements frequently change. Where plain shelves for folded clothing were initially sufficient, compartmentalised organisation for underwear, socks, or accessories is often needed later on. In this scenario, retrofitting internal pull-outs is an ideal solution.

When searching for fittings and components as an alternative to IKEA Pax or as an upgrade for similar modular wardrobe systems, strictly adhering to the exact technical specifications of the carcase is essential. Compatibility is not determined by aesthetics, but by millimetre dimensions, hole patterns, and the load capacity of the runners used. This guide explains the technical principles for professionally integrating drawer systems into existing wardrobes.

Dimensional Requirements and Compatibility: System 32

To fit components compatible with IKEA Pax or other standardised furniture ranges, understanding the carcase geometry is vital. The industry operates with fixed drilling grids.

The Internal Width (Clear Opening)

The external dimension of a wardrobe (for example, 50 cm, 75 cm, or 100 cm) is irrelevant when installing runners. What matters is the internal width: the exact clearance between the left and right interior walls. With a standard side panel thickness of 18 mm, a 100 cm carcase provides an internal width of 964 mm. Selected runners and drawer box widths must match this dimension precisely, otherwise the guides will bind and jam.

Hole Pattern and Carcase Depth

Most modern wardrobes utilise System 32. This means the pre-drilled holes in the side panels are spaced exactly 32 mm apart with a diameter of 5 mm. System screws (also known as Euro screws) fit securely into these drill holes to mount the runners.

Depth is another critical factor. A wardrobe with a nominal depth of 58 cm usually provides an internal usable depth of roughly 550 mm to 570 mm (depending on back panel construction and door clearance). Runners with a nominal length of 500 mm are ideal for this size. For shallower hallway units with an external depth of 35 cm, the usable internal depth is around 330 mm. Here, appropriately shorter hardware, such as drawer runners 300 mm, is required.

Choosing the Correct Runner Mechanism

During assembly, the wardrobe carcase acts as the chassis, while the runners are the running gear that must be matched to the total weight and the intended motion. Multiple technical designs are available when selecting drawer runners.

Extension Type: Full Extension vs Single Extension

A full-extension runner pulls out 100% from the carcase, meaning the drawer length matches the travel distance. This provides complete access to all contents right into the furthest corner, which is especially practical for deep wardrobes (58 cm). Fitting drawer runners full extension generally requires ball-bearing telescopic runners or concealed undermount slides.

A single-extension runner (part extension) opens to approximately 75% to 80% of its depth. The rear part of the drawer remains inside the carcase. This variant is mechanically simpler and is commonly found in standard roller drawer runners, where plastic rollers travel inside an epoxy-coated metal profile.

Load Capacity and Weight Ratings

For lightweight clothing, standard runners with a load capacity of 20 kg to 25 kg are sufficient. However, if heavy items such as tools, thick winter coats, or storage files are stored in the drawers, this rating will not suffice. In these situations, installing heavy duty drawer runners is essential. These components feature thicker material gauges and are certified for loads of 45 kg or more.

Damping, Opening Mechanisms, and Internal Accessories

Alongside pure load capacity, the kinematics of the runner define user convenience. Two distinct technical mechanisms are frequently confused here.

Soft-Close vs Push-to-Open

Soft-close (or self-closing with damping) catches the drawer during the final centimetres of closing. An integrated hydraulic damper absorbs the momentum while a spring pulls the drawer smoothly and quietly into its fully closed position. Soft close drawer runners require a traditional furniture handle or pull to open.

Push-to-open (often referred to as tip-on) functions as the exact opposite. This is an ejection mechanism designed for handleless fronts. Light pressure on the drawer front releases a tensioned spring that pushes the drawer forward by a few centimetres. Push to open drawer runners typically do not feature soft-close damping, as the closing momentum is required to re-tension the spring mechanism for the next opening cycle.

Functional Additions for Wardrobe Interiors

To prevent belts, jewellery, or smaller items from sliding around during dynamic opening and closing, the base panel is often fitted with an anti-slip drawer mat. This can be cut to the exact internal dimensions using a utility knife. If a specific section of the wardrobe needs to be secured against unauthorised access (such as for private documents), the front panel can be retrofitted with a drawer lock. This requires drilling a hole through the front panel to house the lock cylinder.

Installation and Retrofitting: Step-by-Step

Fitting compatible components requires precision. For installation, you will need a cordless screwdriver, a PZ2 bit, a tape measure, a try square, and a bradawl if necessary.

1. Determine vertical positioning: Establish the height at which the runners will sit within the System 32 grid. Ensure wardrobe door hinges (commonly with a 35 mm cup diameter) do not obstruct the drawer path.
2. Mount the cabinet profile: Screw the carcase runner into the 5 mm side wall holes. Use dedicated Euro screws (typically 6.3 x 13 mm) for this purpose, as they provide the highest pull-out resistance in chipboard.
3. Attach the drawer profile: Fix the matching runner component to the drawer itself. With undermount runners, the drawer box is simply placed onto the profiles and engaged via locking clips on the underside of the base.
4. Adjustment: Insert the drawer. Quality fittings feature adjustment wheels for tilt and vertical height alignment (usually +/- 2 mm) to achieve uniform gap spacing.

Frequently Asked Questions (FAQ)

What runner length do I need as an alternative for 58 cm deep IKEA Pax wardrobes? With a nominal carcase depth of 58 cm, the usable internal depth is approximately 550 mm. The correct runner length is 500 mm. Longer runners will hit the rear panel, whilst shorter runners waste valuable internal space.

Can I simply replace single-extension runners with full-extension runners? Yes, provided the hole pattern and side clearance (the space between the drawer side and wardrobe wall, typically 12.7 mm for side-mounted ball-bearing slides) match. You must remove the old cabinet profile and fix the new runner horizontally along the same row of holes.

Why is my retrofitted drawer not closing flush with the wardrobe? This is usually caused by incorrect setback positioning of the cabinet runner. If the runner is screwed too close to the front edge of the side panel, the drawer front will protrude. Check the installation dimension in the runner's technical drawing (frequently 37 mm from the front edge to the first fixing hole).