To meet UK standards, your mezzanine staircase must follow various regulations. These consist of rules for structural safety, fire safety, accessibility, and staircase sizes. Sticking to these rules helps ensure safety and prevents legal problems.

Structural Safety Compliance

The first step in any mezzanine staircase project is ensuring structural safety. This involves checking how much weight the staircase can bear. It should support personnel, equipment, and materials safely.

Following Approved Document A: Structure is the key to ensuring mezzanine stairs can safely handle imposed and dead loads. This guidance requires designers to adopt Eurocodes EN 1990 and EN 1991-1-1. For office mezzanines, they should apply an imposed load allowance of at least 1.5 kN/m². It also sets out checks on beam, connection and support detailing to prevent deflection, buckling or collapse.

To meet this requirement, collaborate with qualified engineers and architects. They will perform load assessments and structural calculations. This helps maintain the staircase’s integrity while following all the required standards. Regular inspections during installation will also help verify that safety measures are being met.

Fire Safety & Accessibility

Ensuring your mezzanine staircase is fire-safe is a critical part of the design process. Approved Document B: Fire Safety Volume 2 (Buildings other than dwellings) shows the fire resistance periods needed for:

• Stair enclosures
• Landings
• And door sets

A staircase for a mezzanine that holds more than 30 people must have fire-resisting construction for at least 30 minutes. It also needs self-closing fire doors on each level. Also account for fire detection, alarms and smoke vents or sprinklers to maintain tenable escape routes.

In addition to fire safety, accessibility is a key consideration. Approved Document M: Access to and use of buildings Volume 2 (Buildings other than dwellings) requires that any stair serving public or staff areas be designed with:

• Handrails on both sides (where the width exceeds 1 m)
• Tactile step nosings
• A consistent step rise throughout

Handrail tops must be 900–1000 mm above the pitch line, and any balustrade must prevent a 100 mm sphere from passing through. Where a level change cannot be avoided, a platform lift or ramp must be provided for wheelchair users.

For more on fire safety and accessibility, check our project management page.

Mezzanine Staircase Dimensions & Design

When designing a mezzanine staircase, you need to stick to specific regulations. These rules ensure safety and functionality.

Approved Document K: Protection from falling, collision and impact specifies for non-domestic staircases:

• A clear flight width of at least 1000 mm between handrails (or walls)
• If the stair exceeds 1000 mm in width, a handrail is required on each side
  • Maximum riser: 190 mm
  • Minimum going (tread depth): 250 mm
  • Rise-to-going relationship: (2R + G) between 550 mm and 700 mm
  • Steepness control: pitch ≤ 42°

Handrail tops should be fixed at 900–1000 mm above the pitch line. They must resist a horizontal load of 0.74 kN/m. Balustrades need to stop a 100 mm sphere from passing through.