Drawers Suitable for Pax Wardrobes: Dimensions, Runners & Installation

September 29, 2025

When retrofitting drawers into modular wardrobe systems, precisely matching the cabinet depth, runner length in millimetres, and the hole spacing pattern is essential for an accurate fit and mechanical stability.

Modular wardrobes, such as the well-known Pax system, feature standardised internal dimensions. This standardisation allows joiners and skilled fitters to rely on fittings and runner systems from third-party manufacturers when customising interiors. Whether replacing defective slides, constructing new internal drawers, or upgrading to premium damping systems, choosing the correct runner requires considering key technical criteria. This guide walks you through the relevant specifications to identify the mechanically and dimensionally correct solution for your cabinet carcass.

Key Buying Criteria for Compatible Wardrobe Drawers

To integrate a drawer runner into an existing cabinet carcass, the physical parameters of the slide must correspond exactly with the available space and intended load.

Cabinet Depth and Runner Length

The nominal length of the runner depends primarily on the clear internal depth of the cabinet carcass. Standard systems are dominated by two main depths:

Cabinets with 58 cm external depth: The usable internal depth here is typically around 560 mm to 570 mm (excluding the back panel and front overlay). Drawer runners 550 mm are ideal for these dimensions to maximise the available space. Alternatively, if space behind the drawer is needed for cabling or lighting transformers, drawer runners 500 mm are used.
Cabinets with 35 cm external depth: These slimline variants (often used in hallways or as shoe storage) provide an internal depth of around 330 mm. Here, drawer runners 300 mm provide the correct technical measurement.

Load Capacity and Weight Rating

Clothing, especially stacks of jeans or heavy winter jumpers, generates substantial weight. Standard runners are usually designed for 25 kg to 30 kg. If wide drawers (e.g. 100 cm carcass width) are planned, standard fittings reach their structural limits. For wide configurations, using dedicated heavy duty drawer runners is recommended, which offer dynamic load capacities ranging from 45 kg up to over 80 kg depending on the model.

System 32 Hole Spacing and Fixings

Most industrially manufactured wardrobe side panels come pre-drilled according to System 32. This means: the vertical distance between drill holes is 32 mm, and the distance from the first row of holes to the front edge of the carcass is standard at 37 mm. The holes typically have a diameter of 5 mm. Runners are secured here using special Euro screws. If pre-drilled holes are absent, the runners must be screwed directly into the engineered wood using standard chipboard screws (3.5 mm or 4 mm diameter).

Overview of Runner Systems: Which Mechanism Fits?

The choice of runner type dictates the running smoothness, user comfort, and the overall construction of the drawer box itself.

Roller runners: A simple, proven system where plastic rollers glide inside an epoxy-coated metal track. They feature a certain amount of lateral play and are mostly built as single extension (partial extension) slides. The advantage lies in their high tolerance for minor assembly inaccuracies. Suitable models are available under roller drawer runners.
Ball bearing runners: Here, steel ball bearings run within a telescopic profile. This system provides exceptionally high lateral stability, precise movement, and is designed for heavy loads. Ball bearing slides are generally screwed to the sides of the drawer box.
Under-mount runners: In this system, the runner is installed invisibly beneath the drawer base. This requires a specific wooden drawer construction (the side panels must extend downwards past the base), but it rewards the user with a completely clean aesthetic, as no metal parts are visible when the drawer is open. Corresponding fittings can be found under under-mount drawer runners.
Extension type: A partial extension runner pulls out to roughly 75% to 80% of its nominal length from the cabinet. The rear section of the drawer remains inside the carcass. A full extension runner, however, pulls out 100%. This provides unrestricted access to the furthest corners of the drawer. For deep wardrobes, this design is strongly recommended. Matching components can be found under full extension drawer runners.

Decision Guide: Which Runner for Which Purpose?

Selecting the right mechanism depends entirely on the specific application within the wardrobe.

If heavy garments are stored in wide carcass units: Choose side-mounted heavy-duty ball bearing runners. The telescopic design prevents runner deflection under maximum load.
If the drawer needs to close silently in a bedroom: A runner with integrated soft-close is required. A hydraulic damper cushions the closing action over the final few centimetres and pulls the drawer shut gently and silently. For this requirement, soft-close drawer runners are ideal.
If internal drawers are concealed behind hinged doors without handles: You need a push-to-open mechanism. Light pressure on the front panel triggers a spring that ejects the drawer forward by several centimetres. Compatible systems can be found under push-to-open drawer runners.

Important technical note: Soft-close and push-to-open are mechanically opposing mechanisms. Damping brakes the movement, whereas an ejector accelerates it. Combining both mechanisms inside a single standard runner is physically not possible in conventional hardware.

Installation Tips: Retrofitting Drawer Runners in Wardrobes

During installation, the wardrobe carcass functions like an oversized coordinate system, where the vertical row of holes acts as the Y-axis and the runner acts as the horizontal X-axis. Millimetre-accurate workmanship is essential to ensure the drawer does not bind or jam later.

Required Tools

Cordless screwdriver
Matching driver bits (typically PZ for chipboard screws or a dedicated bit for Euro screws)
Tape measure and pencil
Short spirit level
Bradawl or small punch

Step-by-Step Installation

Define the height: Determine the desired installation height for the drawer. Mark the corresponding hole in the front row of drillings.
Position the carcass runner: Position the carcass component of the slide. With System 32 hole patterns, the distance to the front edge aligns automatically. Without pre-drilled holes, the runner must be levelled precisely (spirit level), and the setback from the front edge (usually 2 mm to 37 mm, depending on front overlay) must be marked identically on both sides.
Fasten into place: Secure the runner first through the front slotted hole. This allows for subsequent fine adjustment. Afterwards, fasten the rear fixing points.
Mount the drawer runner: For telescopic runners, separate the inner profile using the release lever. Screw this profile flush along the lower outer edge of the wooden drawer.
Insert the drawer: Guide the drawer horizontally into the cabinet carcass until the profiles audibly engage.

Frequently Asked Questions (FAQ)

Which runner length do I need for a 58 cm deep wardrobe? For a carcass with an external depth of 580 mm, you require runners with a nominal length of 500 mm or 550 mm. The usable internal depth minus the back panel is approximately 560 mm; therefore, the runner must not exceed this dimension.

What is the difference between roller runners and ball bearing runners? A roller runner uses plastic wheels running in a metal profile and is mostly produced as a partial extension slide. A ball bearing runner consists of interlocking metal profiles with steel ball bearings, offering higher load capacity, less lateral play, and is frequently designed as a full extension slide.

Can I combine a push-to-open runner with soft-close damping? No, in standard hardware these functions are mutually exclusive. Push-to-open uses a spring to eject the drawer, whereas damping (soft-close) brakes the drawer and pulls it shut. An ejector would work against the resistance of the damper.

Which screws should I use for pre-drilled holes in the wardrobe? If the cabinet has pre-drilled holes with a 5 mm diameter, dedicated Euro screws must be used. Standard chipboard screws (3.5 mm or 4 mm) will not achieve sufficient grip in these larger holes.