What the result helps you understand
Ladder details often get copied from old drawings even when the ladder type or length has changed. A simple geometry check helps catch spacing and width errors before fabrication.
Access & Safety
AS 1657 Ladder Rung & Handrail Geometry Checker
Check selected rung or tread spacing, clear width and step-type ladder handrail clear space for common AS 1657 ladder arrangements.
“The fabricator has proposed rung spacing and ladder width. Are those dimensions within the quick geometry ranges for this ladder type?”
Core formulae
Ladder rung, tread and handrail detail screen
Step-type tread spacing
200 mm ≤ spacing ≤ 300 mmSingle-stile rung spacing
200–300 mm or 250–300 mm, depending on ladder lengthStep-type clear ladder width
450 mm ≤ width ≤ 750 mmStep-type handrail clear space
550 mm ≤ clear space ≤ 750 mmThe applicable single-stile and step-iron rung-spacing screen changes with ladder length.
Simple arrangement sketch
Ladder spacing and clear width
1
Ladder detail geometry
Select the ladder type first because the applicable rung/tread spacing and width checks change with the arrangement and length.
Results
Inclined step-type ladder geometry screen
Applicable spacing screen200–300 mm
Entered spacing275 mm
Within spacing screen.
Applicable clear-width screen450–750 mm
Entered clear width500 mm
Within width screen.
Handrail clear-space screen550–750 mm
Entered handrail clear space650 mm
Within handrail screen.
The entered detail geometry passes the numerical checks included for this ladder type
Continue with pitch, clearances, landings, fall protection, access openings and the other requirements for the selected ladder arrangement.
Detail-only boundary
Not checked: ladder pitch, maximum lengths, landings, cages, fall-arrest systems, clearances behind and around rungs, entry/exit arrangements, gates, structural capacity, slip resistance or whether this ladder type is appropriate for the access task.
Job-file record
Save the calculation, not just the number.
Copy a permalink that reloads these inputs, or download a PDF record with inputs, visible results, assumptions, a sensitivity note, date and disclaimer.
Know where the quick calculation stops
It does not check ladder pitch, maximum lengths, landings, cages, fall-arrest systems, rung clearances, access openings, gates, structural capacity, slip resistance or whether the selected ladder type is appropriate.
Important boundary
A calculator can show the arithmetic. It cannot establish every requirement that applies.
Confirm the actual equipment, loading, materials, condition, jurisdiction, contractual requirements, standard edition and current project documentation before using the result for design, repair, testing or lifting decisions.
Ask an engineer about this calculation →