Scaffolding Calculator
Enter the wall perimeter and scaffold height to get the area plus tube, coupler and board quantities.
Quick answer
With the default inputs: Wall perimeter 80 · Scaffold height 20 · Scaffold type Double-row external etc.Scaffold area 1600.0 m²
Edit the inputs below to recalculate.Inputs
Result
Scaffold area
1600.0m²
| Lifts @1.8 m | 12lifts |
| Scaffold area | 1600.0m² |
| Steel tube | 8.00t |
| 6 m tubes | 359bars |
| Couplers | 2,880pcs |
| Scaffold boards | 448.0m² |
| Safety netting | 1680.0m² |
| Wall ties | 108pcs |
Tube assumes Φ48×3.0 at 3.84 kg/m. The scaffold design must be prepared to JGJ 130 by a qualified engineer.
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Enter a target result; the other inputs stay fixed and this one is worked out.
Formula
| Scaffold area | A = perimeter × height |
| Steel tube | W = A × kg per m² × type factor |
| Couplers | N ≈ A × 1.8 |
| Boards | A_board ≈ A × 0.28 |
| Lifts | lifts = ceil(height ÷ 1.8) |
An 80 m perimeter at 20 m high: 1,600 m² of scaffolding, 8 t of tube at 5 kg/m², roughly 2,880 couplers and 448 m² of boards.
How to work it out
- Measure the outer face line of the external wall — not the building perimeter and not the grid line. Balconies, canopies and projecting eaves are measured on their own outer face.
- Set the height: external ground level to the underside of the eaves; up to the top of the parapet where there is one; to the eaves, not the ridge, on pitched roofs.
- Scaffold area = outer face length × height. Openings and balconies are not deducted — this is where scaffold measurement differs fundamentally from floor area.
- Take steel content by system: double scaffold 4-6 kg/m², single 3-4, full hall 8-12. The figure already covers standards, ledgers, bracing and base rails.
- Total steel = area × content; couplers at 15-20% of steel mass or 1.5-2 per m²; decking by laid area, normally one working lift plus one protective lift.
Where it goes wrong
- Deducting windows and doors — scaffolding is measured on the vertical projection of the facade and the scaffold still runs past every opening.
- Using floor area as scaffold area — floor area projects the structural envelope horizontally, scaffolding projects the outer face vertically; the difference is height plus projecting elements.
- Measuring height only to the eaves — parapets measure to their top, and rooftop plant such as tanks and lift motor rooms needs separate consideration.
- Ignoring the high-level allowance — many regions add a premium above 24 m, and above 50 m the scaffold is a major hazard installation needing expert review.
Material and cost
Scaffold complete (tube and coupler hire plus erection and dismantling) 20-45 CNY/m², including netting and decking. Tube hire about 4-6 CNY/m per month, couplers 0.3-0.5 each per month.
On site
- Ground-supported scaffolding over 24 m is a major hazard installation and over 50 m needs expert review; the method statement and acceptance records are mandatory documents.
- Ties must connect to structure, never to window frames, balustrades or pipes; three lifts by three bays is the usual spacing.
- Hardstand and drain the scaffold base, and use sole plates and base jacks. Standing standards directly on backfill is the leading cause of collapse.
Basis
- JGJ 130-2011 Technical code for safety of steel tubular scaffold with couplers
- GB 50854-2013 Code for measurement of building works, Appendix S (preliminaries)
- MOHURD regulation on safety management of hazardous sub-projects (2018 No.31)
FAQ
Is scaffold area measured on the wall face or the projection?
External scaffolding is the outside perimeter multiplied by the scaffold height, which is the vertical projection of the wall. Openings are not deducted. Single-row scaffolds count at half rate, internal scaffolds by wall projection, and full-hall scaffolds by internal floor area.
When must a double-row scaffold be used?
Single-row scaffolding is limited to 24 m and only where the wall can take reliable ties. Above 24 m a double-row system is required. In China, ground-supported tube scaffolding at 24 m or more is classified as high-risk work needing an expert-reviewed method statement, and above 50 m cantilevered or climbing systems must be used.
Where does 4-6 kg/m² of tube come from?
Empirical content for a double-row scaffold at 1.8 m lift and 1.5 m bay, including standards, ledgers, transoms, bracing and base rails, works out at roughly 4-6 kg of tube and 1.5-2 couplers per square metre of elevation. Netting, boards and toe boards are counted separately.
Cite this page
Use this format in reports, method statements or coursework. The link is permanent.
Building Calculator. Scaffolding Calculator. 2026-10-25. https://jianzhujisuan.com/en/scaffolding
Results are estimating aids only and are not a design basis. Construction and final accounts must follow the drawings, the applicable standards and an approved method statement. Anything affecting structural safety, shoring or falsework must be checked by a suitably qualified engineer.