Scaffold Load Rating Calculator

Duty rating from workers, tools, and material on platform.

Platform length (ft)

Platform width (ft)

Number of workers

Tool / equipment weight (lbs)

Material weight (lbs)

Tab to move between fields

Total platform load (lbs)

550

Duty rating (1=Light, 2=Med, 3=Heavy, 4=Special)

Load per sq ft (psf)15.7

Required capacity w/ 4:1 SF (lbs)2,200

Duty utilization (%)62.9%

Remaining capacity (lbs)325

How to Use This Calculator

Enter platform length (ft) and platform width (ft).
Set the number of workers, tool/equipment weight (lbs), and material weight (lbs) on the platform.
Review total load (lbs), load per sq ft, duty rating (light/medium/heavy), and required capacity.
Never exceed the rated capacity -- exceeding duty rating is a leading cause of scaffold collapses.

How the result changes with Tool / equipment weight (lbs)

Tool / equipment weight (lbs)	Total platform load (lbs)	Duty rating (1=Light, 2=Med, 3=Heavy, 4=Special)
500	1,000	2
1,750	2,250	3
3,250	3,750	4
4,500	5,000	4

Platform length (ft): Length of the scaffold platform (typically 7 or 10 ft).
Platform width (ft): Width of the scaffold platform (typically 5 ft for standard frame).
Number of workers: Workers on the platform. OSHA assumes 250 lbs each (body + PPE + hand tools).
Tool / equipment weight (lbs): Weight of power tools and equipment on the platform.
Material weight (lbs): Weight of construction materials stored on the platform (brick, mortar, etc.).

Total platform load (lbs): Combined weight of workers, tools, and materials.
Load per sq ft (psf): Pounds per square foot on the platform.
Duty rating (1=Light, 2=Med, 3=Heavy, 4=Special): OSHA duty classification: 1=Light (25 psf), 2=Medium (50 psf), 3=Heavy (75 psf), 4=Special (engineering required).
Required capacity w/ 4:1 SF (lbs): Minimum scaffold rated capacity per OSHA 4:1 safety factor.
Duty utilization (%): How much of the duty rating capacity is being used.
Remaining capacity (lbs): Additional weight that can be added before exceeding the current duty rating.

Identify Input Parameters
4 parameters
Platform length (ft) = 7, Platform width (ft) = 5, Number of workers = 2, Tool / equipment weight (lbs) = 50 = 5 input(s) provided
Calculate Total platform load
Total platform load = workerWeight + toolWeight + materialWeight
550 = 550
Calculate Duty rating
Duty rating
1 = 1
Calculate Load per sq ft
15.7 = 15.7
Calculate Required capacity w/ 4:1 SF
Required capacity w/ 4:1 SF = totalLoad * 4
2200 = 2200