Office Sideboard for Lever Arch Files: Required Depth and Height Dimensions

A sideboard for standard lever arch files requires an internal clearance of at least 320 mm in height and 290 mm in depth, which generally dictates an external depth of 350 mm to 400 mm once the back panel and front door thickness are accounted for.

When furnishing office spaces or a home study, furniture selection often falls short due to inaccurate dimensions and insufficient static load capacity. A standard lever arch file (such as DIN 821) measures 318 mm in height and 285 mm in depth. The spine width varies between 50 mm and 80 mm. These rigid dimensions dictate the technical specifications for chests of drawers & sideboards intended to serve as archiving solutions.

A sagging shelf is like a flat tyre on a transport trolley – it halts smooth daily operations and leads to long-term material damage across the entire carcass. For this reason, considering external dimensions alone is never enough. The construction, the chosen furniture fittings, and the material thickness of the shelves are critical for long service life.

Key Purchasing Criteria for Office Sideboards

To store lever arch files professionally and securely, various technical parameters across carcass construction and hardware planning must align perfectly.

Internal vs. External Dimensions

The external dimension of a piece of furniture never equals the usable internal space. The difference stems from the material thickness of the fronts, the back panel construction, and the door inset.

• Depth: A file requires 285 mm of clear standing space. Adding 5 mm clearance to the back panel, a grooved-in back panel (approx. 10 mm to 15 mm offset from the rear edge), and a door thickness of 19 mm results in an absolute minimum external depth of around 330 mm. A 35 cm deep chest of drawers is therefore the tightest dimension that functions for lever arch files.
• Height: The internal compartment height must be strictly 320 mm to prevent files from catching on the upper edge. In planning, storage is calculated in "FH" (file heights). A 2-FH sideboard requires a usable internal clearance of at least 660 mm. Including the plinth, base panel, intermediate shelf, and top panel, the overall height of such a unit usually measures 750 mm - 850 mm.

Load Capacity and Deflection

A fully loaded lever arch file weighs between 2.5 kg and 3.0 kg. Along one running metre (1000 mm), approximately 12 to 13 wide files can be accommodated, which corresponds to a continuous static load of nearly 40 kg.

• Material thickness: Shelves made of standard chipboard should be at least 19 mm thick for widths of 800 mm or more. With a 16 mm thickness, visible deflection threatens under continuous load.
• Shelf supports: Cylindrical metal shelf supports are mandatory for heavy loads. These typically engage in 5 mm diameter drill holes set into the side panels using the standardised System 32 (32 mm hole spacing). Plastic supports tend to shear under the weight of paper archives.

Fittings and Hinge Technology

Sideboard doors conceal the archive, but they must not obstruct access.

• Concealed hinges: Concealed cup hinges with a standard cup diameter of 35 mm are used for cabinet doors.
• Mounting types: With a full overlay, the door sits over the carcass edge. This maximises usable internal depth. An inset door (where the door sits flush between the carcass sides) reduces the usable internal depth by the full door thickness (usually 16 mm or 19 mm). This must be added to your depth calculations.
• Opening angle: A standard opening angle of 110° is sufficient for standard shelf compartments. If internal drawers are to be fitted behind the doors, hinges with a 155° or 165° opening angle are required so the full extension runners do not catch on the open door.

Overview of Depths and Configurations

Depending on room size and archiving requirements, different depth specifications are available. The choice of external depth significantly affects functionality.

• Depth 300 mm: A 30 cm deep chest of drawers is technically unsuitable for standard lever arch files. The usable internal depth here is at most 260 mm to 270 mm. These units are only suitable for paperbacks, catalogues, general stationery, or as slim hallway storage.
• Depth 350 mm: This is the functional minimum for files. The doors close flush, with the files resting closely against the back panel. Ideal for narrow corridors or compact home offices where every centimetre counts.
• Depth 400 mm: A 40 cm deep chest of drawers provides the optimal compromise. Files have adequate clearance behind them, allowing better air circulation and preventing paperwork from catching when closing the doors.
• Depth 450 mm: If you plan to store larger equipment (routers, small printers) or archive boxes alongside files, a 45 cm deep chest of drawers is the best option. This leaves ample room behind the files for concealed cable management.

Which Dimensions for Which Scenario? (Decision Guide)

Selecting the correct sideboard depends on the specific setup in your office or home workspace.

When space is severely limited: In narrow walkways or directly behind an office chair, a 35 cm deep chest of drawers is the right choice. Ensure you use full overlay hinges here to avoid losing a single millimetre of the already limited internal depth.

When a high-end look is required: In corporate practices or reception areas, high-gloss sideboards are popular choices. A depth of 400 mm to 450 mm is recommended here. The more generous depth provides a more substantial, premium presence. Furthermore, doors fitted with push-to-open mechanisms are much easier to adjust when files are not pressing against the front from the inside.

When the unit serves as a room divider: If the sideboard stands freely in the room, for example as a side boundary to an office desk or a height-adjustable desk, the rear must feature a solid decorative back panel (usually 16 mm to 19 mm thick). This significantly reduces internal depth. In this scenario, the external depth must be at least 400 mm to accommodate standard files.

When budget is the priority: Budget sideboards can also accommodate files provided the structural integrity is sound. Check the shelf thickness prior to assembly. If shelves are only 15 mm or 16 mm thick, limit the compartment span to a maximum of 600 mm using vertical centre dividers to prevent sagging.

Installation and Assembly Tips for Heavy Loads

A sideboard loaded with hundreds of kilograms of paper requires particular care during assembly. High-grade furniture fittings cannot perform properly if connections are not assembled correctly.

1. Stabilise the back panel: The back panel provides essential racking resistance (shear strength) for the entire carcass. On basic units, the back panel is often merely nailed. For heavy loads of lever arch files, screw the back panel at regular intervals (approx. every 150 mm) using pan-head screws (e.g. 3 x 15 mm).
2. Level with a spirit level: A fully loaded sideboard will not tolerate uneven floors. If the carcass stands out of level, door gaps will misalign and hinges will wear unevenly. Use height-adjustable cabinet feet to level the unit precisely before loading it.
3. Adjust the hinges: Once the unit is loaded with files, the carcass may settle slightly, causing doors to drop. This can be corrected via the cross mounting plate inside the cabinet. The front screw on the hinge arm adjusts the lateral reveal, the rear screw sets the depth, and the screws on the mounting plate itself regulate vertical height.
4. Anti-tip wall fixing: A sideboard measuring 800 mm wide with 2 file heights can easily exceed 80 kg when filled. Opening both doors simultaneously shifts the centre of gravity forward. Anchoring the unit to the wall (using heavy-duty brackets and wall plugs) is mandatory in commercial environments and strongly advised for home offices.

FAQ – Frequently Asked Questions About Office Sideboards

Does a standard lever arch file fit into a 30 cm deep sideboard? No. An external depth of 300 mm results in a maximum usable internal depth of 260 mm to 270 mm. A standard file is 285 mm deep, meaning the doors would not close.

How much vertical clearance is required between shelves for files? The clear internal height (the gap between the lower and upper shelf) must measure at least 320 mm. A clearance of 330 mm is recommended to tilt and retrieve files comfortably.

What load capacity must an office shelf support? Expect approximately 30 kg to 40 kg per running metre of files. An 800 mm wide shelf should therefore be rated for a static distributed load of at least 35 kg.

Why do my sideboard doors catch after loading the files? The significant weight of paperwork causes the carcass to settle slightly, especially on uneven floors. This settling alters door gaps. Readjust the hinges using the adjustment screws on the mounting plate once the unit is fully loaded.

What hinge opening angle is best for an office cabinet? For traditional sideboards with shelves, an opening angle of 110° is the technical standard. It allows convenient access to all files without the door obstructing retrieval.