How to Choose the Right Cat Ladder

Measure the Climb Height & Landing Point

Measure vertically from grade or finished floor to the point where the climber steps off — the roof edge, parapet top, tank roof or platform, not the eaves or the wall face. That single number drives sections, guarding and platforms.

• • Single sections run up to 25 m — our factory maximum for one piece.
• • EN ISO 14122-4 caps one flight at 10 m; longer climbs are split, and we add a rest platform once the climb passes 6 m.
• • Confirm the landing direction — it decides the platform, walkway and gate in Step 4.
• • Check obstructions: a standoff of 150–250 mm must stay clear of the wall or tank shell.

Fix the Governing Standard

The destination market, not the factory, decides the rules. Tell us where the cat ladder will be installed and we build, test and certify to that regime — the details differ more than most buyers expect.

• • UK, EU and most international: EN ISO 14122-4 / BS 4211 — rungs 225–300 mm, fall protection above 3 m.
• • US: OSHA 1910.23 rungs 254–356 mm; OSHA 1910.28(b)(9) requires a ladder safety system or PFAS on new climbs above 24 ft — existing caged ladders are grandfathered only until 2036-11-18.
• • Australia / NZ: AS 1657 — rungs 250–300 mm.
• • Our standard build at 225–230 mm centres sits inside every regime above.

Choose the Material

Match the material to the environment the cat ladder will live in, not to a price list. Getting this wrong is the most expensive retrofit in access steelwork.

• • Q235B hot-dip galvanized steel, 85–100 µm to ISO 1461 — the default for outdoor and industrial routes.
• • SS304 for food and pharma hygiene; SS316 where coastal chloride attacks coatings.
• • Aluminium where handling weight matters; GRP where the route passes live electrical equipment — non-conductive by nature.

Compare the full options on galvanized steel, stainless, aluminium and GRP pages.

Configure Cage, Platform, Walkway & Gate

Configuration is the safety layer around the climb. Specify each element against the route the climber actually takes, and rate every rung to 1.5 kN whatever you choose.

• • Cage — hoops at ≤1500 mm centres, first hoop at 2.2 m (our factory spec).
• • Platform — rest landings on long climbs and a safe step-off at the top.
• • Walkway — whenever crews walk onto a roof edge, parapet or tank top.
• • Gate — a self-closing safety gate at every exit opening.

See cage, platform and walkway & gate configurations for build details.