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Key Points for Selecting Grating Stair Treads

Time:2021-11-23

1. Dimensional Standards 

The standard widths for steel grating stair treads are 700mm, 800mm, and 900mm. The minimum allowable width is 600mm, and the maximum width should not exceed 1200mm.

Single Person Traffic: For stairs intended for single-person use, the clear width between the two stringers or guardrails shall be not less than 600mm.

Heavy Traffic / Egress: If the stairs are subject to frequent cross-traffic involving multiple people simultaneously or serve as a personnel evacuation route, the width shall be increased to 1200mm.

2. Load Capacity & Deflection 

The nosing (leading edge) of the stair tread must withstand a concentrated load of 1.5 kN.

For widths ≤ 1200mm: The 1.5 kN load shall be applied on a 100mm × 100mm area.

For widths > 1200mm: An additional 1.5 kN load shall be applied at intervals of 600mm along the width.

Deflection Limit: Under these loads, the maximum deflection of the grating shall not exceed 1/500 of the clear span (the distance between supports).

3. Installation Methods 

There are two primary methods for securing the stair treads:

Welded Fixing: the tread is directly welded to the supporting steel stringer.

Advantage: More economical and durable.

Note: No side plates are required, but the treads cannot be easily disassembled.

Bolted Fixing: requires thicker end plates (side plates) with pre-drilled holes for anchoring bolts.

Advantage: Allows for disassembly and repeat usage/recycling.

4. Application & Cost-Saving Tips 

Nosing (Front Edge): If the staircase experiences high pedestrian traffic, select treads with a front nosing for safety. If traffic is light, you may omit the nosing to reduce costs.

Mounting Choice:

If using bolted fixing, ensure the treads come with drilled end plates.

If using direct welding, there is no need for thickened end plates.