Calculating the load classes of a scaffold correctly
Scaffolding load classes are among the most important, yet at the same time most frequently misunderstood, fundamentals of scaffolding construction. They determine the loads that a scaffold may safely bear per level – in other words, how many people may work on it at the same time, whether materials may be stored on it, and which types of work are permitted in accordance with the standards.
Scaffolding load classes – interactive calculator
Calculate load classes, understand load classes, access the practical table – in accordance with DIN EN 12811–1.
Calculation details
Recommended load class
Alle Lastklassen nach DIN EN 12811‑1 im direkten Vergleich:
| Load class | Permissible load | Typical uses | Permitted | Not permitted |
|---|---|---|---|---|
| LK 1 | 0,75 kN/m² ≈ 75 kg/m² | Routine checks, inspections | ✓ People, hand tools | ✕ Materials storage |
| LK 2 | 1,50 kN/m² ≈ 150 kg/m² | Painting, cleaning | ✓ 1–2 people, light tools | ✕ Pallets, sacks, insulation boards |
| LK 3 | 2,00 kN/m² ≈ 200 kg/m² | Plaster, ETICS, façade | ✓ Several people + equipment | - |
| LK 4 | 3,00 kN/m² ≈ 300 kg/m² | Natural stone, heavy materials | ✓ Heavy equipment, machinery | - |
| LK 5 | 4,50 kN/m² ≈ 450 kg/m² | Industry, plant engineering | ✓ Heavy-duty operation | - |
| LK 6 | 6,00 kN/m² ≈ 600 kg/m² | Special loads, heavy-duty assembly | ✓ Maximum load | - |
Welche Lastklasse für welche Arbeit? Praxisübersicht nach Gewerk:
| Type of work | Load class | Permissible load | Note |
|---|---|---|---|
| Inspection round / Inspection | LK 1 | 0,75 kN/m² | Inspection only, no tools |
| Painting work (excluding materials store) | LK 2 | 1,50 kN/m² | Max. 1–2 people + paint bucket |
| Cleaning work | LK 2 | 1,50 kN/m² | Lightweight equipment permitted |
| Minor maintenance work | LK 2 | 1,50 kN/m² | No pallets / sacks |
| Plastering work | LK 3 | 2,00 kN/m² | Most common construction defects in residential buildings |
| External Thermal Insulation Composite System (ETICS) / Façade insulation | LK 3 | 2,00 kN/m² | + Note the width class W09 |
| General façade work | LK 3 | 2,00 kN/m² | Standard detached house / residential construction |
| Natural stone / heavy tiles | LK 4 | 3,00 kN/m² | Allow for heavier materials |
| Industry / Plant Engineering | LK 5 - 6 | 4,50 - 6,00 kN/m² | Involve a structural engineer |
Scaffolding load classes – interactive calculator
Calculate load classes, understand load classes, access the practical table – in accordance with DIN EN 12811–1.
Number of people on site 2 people Load (kg) 80 kg Scaffolding bay length (m) Scaffolding width (m)Calculation details
Passenger load2,0 kNmaterial load0,8 kNTotal load2,8 kNScaffold area1,83 m²Area load1,53 kN/m²Recommended load class
Load class 3Baustellen-Standard – 2.00 kN/m² Plastering, ETICS and façade work✓ Load class sufficient for this combination LK 1= walkingLK 2 = workingLK 3 = working + materialsLK 4 – 6= industrial / specialFree consultationBuy scaffoldingA direct comparison of all load classes in accordance with DIN EN 12811–1:
All LK 1 – 3 (Residential) LK 4 – 6 (Industrial)| Load class | Permissible load | Typical uses | Permitted | Not permitted |
|---|---|---|---|---|
| LK 1 | 0.75 kN/m² ≈ 75 kg/m² | Routine checks, inspections | ✓ People, hand tools | ✕ Materials storage |
| LK 2 | 1.50 kN/m² ≈ 150 kg/m² | Painting, cleaning | ✓ 1–2 people, light tools | ✕ Pallets, sacks, insulation boards |
| LK 3 | 2.00 kN/m² ≈ 200 kg/m² | Plaster, ETICS, façade | ✓ Several people + equipment | - |
| LK 4 | 3.00 kN/m² ≈ 300 kg/m² | Natural stone, heavy materials | ✓ Heavy equipment, machinery | - |
| LK 5 | 4.50 kN/m² ≈ 450 kg/m² | Industry, plant engineering | ✓ Heavy-duty operation | - |
| LK 6 | 6.00 kN/m² ≈ 600 kg/m² | Special loads, heavy-duty assembly | ✓ Maximum load | - |
Which load class for which job? A practical guide by trade:
| Type of work | Load class | Permissible load | Note |
|---|---|---|---|
| Inspection round / Inspection | LK 1 | 0,75 kN/m² | Inspection only, no tools |
| Painting work (excluding materials store) | LK 2 | 1,50 kN/m² | Max. 1–2 people + paint bucket |
| Cleaning work | LK 2 | 1,50 kN/m² | Lightweight equipment permitted |
| Minor maintenance work | LK 2 | 1,50 kN/m² | No pallets / sacks |
| Plastering work | LK 3 | 2,00 kN/m² | Most common construction defects in residential buildings |
| External Thermal Insulation Composite System (ETICS) / Façade insulation | LK 3 | 2,00 kN/m² | + Note the width class W09 |
| General façade work | LK 3 | 2,00 kN/m² | Standard detached house / residential construction |
| Natural stone / heavy tiles | LK 4 | 3,00 kN/m² | Allow for heavier materials |
| Industry / Plant Engineering | LK 5 - 6 | 4,50 - 6,00 kN/m² | Involve a structural engineer |
Load classes for scaffolding, explained simply
In practice, incorrectly selected load classes can quickly lead to overloading, safety risks and legal problems. Conversely, selecting the correct load class ensures clear procedures, safe working conditions and the smooth running of projects. This is precisely where this guide comes in.
On this page, we explain in a clear and practical way,
- what scaffolding load classes are,
- in which the individual classes differ,
- which load class is required for which tasks
- and how to avoid common planning and implementation errors.
Whether it’s façade renovation, painting or the installation of an external thermal insulation composite system (ETICS): with the right knowledge, you can make informed decisions and ensure that your scaffolding is used safely, in accordance with standards and efficiently.
Differences between scaffolding load classes
The difference between load classes 1, 2 and 3 lies in the permissible load per scaffolding level and, consequently, in the types of work permitted on the scaffolding. This is regulated by DIN EN 12811–1.
Scaffolding load classes 1 – 3: a direct comparison (DIN EN 12811–1)
Scaffolding load classes – overview
What load can be placed on which scaffolding? EN 12811 · Version 04/2026
cetrac.com · Second-hand branded scaffolding from 10 €/m² Stand:04/2026 Prices may vary · Leipzig
Further reading:
Load classes explainedFree consultation
Step-by-step: Calculating the load class correctly
1. Record all loads (per scaffold level)
Du berücksichtigst immer die ungünstigste Nutzungssituation.
(a) Passenger load
- Practical value: 1 person ≈ 1.0 kN (≈ 100 kg)
- Example: 2 people → 2.0 kN
(b) Material load
- Bags (plaster, mortar, insulation)
- Farbeimer, Fliesen, Werkzeuge
Gewicht in kg → in kN umrechnen
Faustformel:
100 kg ≈ 1,0 kN
c) Equipment / Machinery
- Mixing equipment, cutting machines, ETICS kits, etc.
2 Convert load to area
DIN distinguishes between surface loads (kN/m²).
Formula:
Total load (kN) ÷ scaffolding area in use (m²) = area load (kN/m²)
Example:
- 2 people → 2.0 kN
- Material → 1.5 kN
- Total → 3.5 kN
Scaffolding area:
- 2.5 m long × 0.73 m wide = 1.83 m²
3,5 kN ÷ 1,83 m² = 1,91 kN/m²
3. Select the appropriate load class in accordance with DIN EN 12811
Typical load classes in practice
Important safety rules (often overlooked)
- The load class applies to each level of the scaffolding, not to the entire scaffold
- Do not stack materials unless specified
- The load class must be shown on the scaffolding sign
- The width class (e.g. W09 for ETICS) is also mandatory
Click here for instructions on how to erect scaffolding correctly:
Putting up scaffolding: Instructions
FAQ: Scaffolding load classes explained simply
Scaffolding load classes specify the maximum load that a scaffold level may safely bear per square metre. They determine how many people may work on the scaffold at the same time, whether materials may be stored on it, and which types of work are permitted in accordance with the standards.
Load classes are specified in DIN EN 12811-1. There are a total of 6 load classes, ranging from light foot traffic (1) to heavy industrial loads (6).
Load class 2 is generally sufficient for simple painting and cleaning work. This allows for 1–2 people using light tools, but does not permit the permanent storage of materials such as pallets or sacks.
Die Lastklasse 3 ist der Standard im Wohnungsbau und bei Fassadenarbeiten wie Putz oder WDVS-Montage. Sie erlaubt mehrere Personen sowie praxisübliche Mengen an Arbeitsmaterial.
The calculation is carried out in three steps:
- Record all loads (people, materials, equipment)
- Divide the total load by the scaffolding area in use → Result in kN/m²
- Select the appropriate load class in accordance with DIN EN 12811
Rule of thumb: 100 kg ≈ 1.0 kN
No – the load class applies to each level of the scaffolding, not to the scaffolding as a whole. This is one of the most common mistakes made in practice.
The load class must be clearly indicated on the scaffolding sign. In addition, the width class (e.g. W09 for ETICS work) must also be specified.
For heavy materials such as natural stone or tiles, load class 4 or 5 is recommended. For industrial applications involving special loads, load class 6 (6.00 kN/m²) is used.
Choosing the wrong load class can lead to overloading, safety risks and legal problems. In the worst-case scenario, the scaffolding could collapse. The correct load class is therefore not merely a recommendation, but a safety requirement.