UK cable tray thickness

UK cable tray thickness varies by duty rating, typically ranging from 12mm for light duty to 80mm for extra heavy duty trays.

Standard Thickness by Duty Rating

In the UK, cable trays are classified by their mechanical duty, which determines the material thickness required for structural integrity:

• Light Duty (SS): Tray depth 12mm or 18mm, suitable for small cable loads and short spans .
• Medium Duty (MRF): Tray depth 25mm, designed for moderate cable loads and standard installation spans .
• Heavy Duty (SRF): Tray depth 50mm, used for larger cable bundles or longer spans where higher load capacity is needed .
• Extra Heavy Duty (XRF): Tray depth 80mm, intended for very heavy cable loads or industrial applications requiring maximum strength . These thicknesses are generally measured as the side rail height or tray depth, which directly affects load capacity, allowable span, and long-term durability .

Material Considerations

Cable trays in the UK are manufactured from steel, stainless steel, or aluminium, and the thickness may vary slightly depending on the material and manufacturer. Ladder, perforated, and wire mesh trays have different structural requirements, so the same nominal width and depth may have different material thicknesses to meet load and safety standards .

Standards and Compliance

UK cable trays are typically manufactured in accordance with BS EN 61537, which specifies requirements for cable tray systems, including mechanical strength, material thickness, and safety . Compliance ensures that trays can safely support cables, withstand environmental conditions, and meet inspection requirements.

Practical Implications

• Selecting the correct thickness is crucial to prevent tray deflection, cable damage, or failure under load.
• Heavier duty trays are recommended for longer spans, high cable density, or industrial environments.
• Always verify the manufacturer's specifications and ensure compatibility with fittings, supports, and installation standards . By following these guidelines, electricians and engineers can ensure safe, durable, and code-compliant cable tray installations in the UK.