What is the minimum platform width for different work activities?

BS EN 12811-1 minimum widths: W06 (600mm, 3 boards) — access and inspection only. W09 (800mm, 4 boards) — light work, painting. W12 (1300mm, 5-6 boards) — general purpose, bricklaying. W15 (1500mm, 7 boards) — general purpose with materials. W18 (1800mm, 8 boards) — heavy duty with material storage. Most working scaffolds use W12 (1300mm).

At what height are guardrails required?

Under the Work at Height Regulations 2005, guardrails are required on all working platforms where a person could fall 2 metres or more. Guardrails must include: a top rail at minimum 950mm height, an intermediate rail (or equivalent) at approximately 470mm, and a toe board at least 150mm high. The gap between top rail and intermediate must not exceed 470mm.

How many platform levels do I need?

Working platforms should be positioned so that work can be carried out comfortably between waist and shoulder height. Typically, platform levels are spaced at 1.5-2.0m intervals. For example, to work on a 6m high wall, you would need platforms at approximately 1.5m, 3.0m, and 4.5m. Each level needs guardrails and access.

What access do working platforms need?

Every working platform must have safe access. For scaffolds: internal ladders through trap doors in the platforms are standard. Ladder access should be within 30m of any working position. Stair towers are required for scaffolds used by many workers or for frequent access. All ladders must extend 1m above the platform they serve.

Can I use a working platform without guardrails below 2m?

Work at height regulations apply from any height where injury could result from a fall. Below 2m, the risk assessment determines what protection is needed. Even at low heights, platforms should have secure edges to prevent trips and falls. Best practice is to provide guardrails on all platforms regardless of height, especially where heavy or awkward materials are handled.

TradeCalculator

Working Platform Calculator — Width, Guardrail & Platform Levels

Calculate working platform requirements per BS EN 12811. Determines minimum platform width, number of levels, guardrail requirements, and access points.

Maximum Working Height

Height of highest work point

Platform Use

Determines minimum platform width

Platform Length

Total length of platform run

How We Calculate This

This calculator determines working platform requirements per BS EN 12811-1, including minimum width, number of levels, and guardrail specifications.

Platform sizing

Width: 600mm (access) to 1800mm (heavy duty with storage)
Levels: Spaced at 1.5-2.0m for comfortable working
Guardrails: 950mm top rail, 470mm intermediate, 150mm toe board
Access: Ladder or stair within 30m of any work point

Frequently Asked Questions

Related Calculators

Scaffold Hire Cost Calculator

Calculate scaffold hire cost from building perimeter, height and hire period.

Scaffold Load Class Calculator

Determine scaffold load class by trade use with platform loading check.

Tower Scaffold Height Calculator

Calculate tower scaffold maximum height from base dimensions with stabiliser requirements.

Scaffold Tie Calculator

Calculate scaffold tie pattern per TG20 with tie type selection.

Scaffold Board Calculator

Calculate scaffold platform boards, toe boards and ladder access per bay.

Last updated: March 2026

All calculations are estimates. Verify with your supplier.