Spiral Durbar Stair Treads – Tapered Pattern 1 Anti-Slip Checker Plate

Our spiral durbar stair treads are tapered Pattern 1 checker plate steps shaped for spiral and helical staircases. Each spiral tread is pressed from S275 mild steel with a raised anti-slip durbar pattern and a 50mm turn up / down nosing, in a 600 x 270mm tapered (kite) profile at 4.5mm thickness. Treads are handed to suit the direction of ascent, so you can specify clockwise or anti-clockwise to match your stair build.

Specification

Material grade: S275 mild steel — minimum yield strength 275 N/mm²

Pattern: Pattern 1 raised durbar anti-slip checker plate

Tread size: 600 x 270mm tapered (kite-shaped) profile

Nosing: 50mm turn up / down

Thickness: 4.5mm

Handing: clockwise ascend or anti-clockwise ascend

Finish: mill finish (self-colour) — paint, prime or galvanise to suit

Choosing the Correct Hand

Spiral treads are directional. A clockwise-ascend tread is used where you turn clockwise as you climb (right hand to the centre column); an anti-clockwise-ascend tread turns the opposite way. Confirm the rotation of your staircase before ordering — fitting the wrong hand will leave the nosing on the incorrect edge. If you are unsure, count the turn direction as you walk up the stairs from the bottom step.

Common Uses

Spiral durbar treads are used on industrial spiral staircases, access towers, mezzanine spiral stairs, tank and silo access, and external spiral fire escapes. The solid durbar checker plate surface gives a slip-resistant, debris-free step that is more robust and easier to clean than open-grid spiral treads.

Fitting & Workability

Each tapered tread is supplied with a pressed nosing ready to weld or bolt to a central column and outer stringer. S275 durbar plate can be drilled, cut and welded with standard steelwork methods and accepts paint, primer or hot-dip galvanising after fabrication where corrosion protection is needed for external use.

Matching Durbar Range

Spiral treads are made from the same S275 durbar plate as our 8×4ft durbar checker plate sheets and 2m × 1m durbar plate. For straight flights see our durbar stair treads and durbar landing plates.

Delivery Information

Spiral durbar stair treads are made to pattern and supplied on a 5–10 working day lead time to mainland UK addresses, with free UK delivery. Treads are sent palletised or by courier depending on quantity — please ensure suitable access is available for delivery.