Tube and fittings
Total tube length and weight (BS EN 39, 48.3 × 4.0 mm)
- where
- total tube length (m)
- number of standards
- length of each standard line (m)
- ledgers, in bay lengths
- bay length (m)
- number of transoms
- transom length (m)
- number of braces
- average brace length (m)
- other tube (m)
- tube weight (kg)
- tube mass per metre (kg/m)
- tube weight (t)
- equivalent 6.4 m (21 ft) tubes
Explain this equation
Totals the tube in a scaffold and its weight, for ordering, transport and checking loads.
Each group of components is its count times its length: standards times their height, ledgers times the bay length, and so on. Adding everything gives the total metres. Standard 48.3 mm scaffold tube with a 4 mm wall weighs about 4.37 kg per metre, so length times that gives kilograms, and dividing by 1000 gives tonnes. Dividing by 6.4 m and rounding up shows the equivalent number of 21 ft tubes.
A straightforward sum of length times count, then weight per metre.
Sense check: about 700 m of tube is about 3.1 tonnes, around 111 full-length tubes.
Watch out: aluminium tube is about a third of the weight; change m if you use it.
Adds up the tube in a scaffold and converts it to weight for transport, crane or hoist planning and wagon loading.
Enter your values to see the result.
Good to know
Steel scaffold tube to BS EN 39 is 48.3 mm outside diameter with a 4.0 mm wall and weighs about 4.37 kg per metre (check: π × (48.3 − 4.0) × 4.0 mm² × 7.85 kg/dm³ ≈ 4.37 kg/m). Aluminium tube of the same diameter is about 1.67 kg/m; change the mass input for aluminium or 3.2 mm wall tube. A standard line usually runs a metre or so above the top platform to carry the guardrails. The 6.4 m figure is only a guide to stock count; real orders mix lengths.
Common mistake
Forgetting guardrail tubes, which on a multi-lift scaffold add two full-length rails per protected lift plus end returns.
Limits
Weight of tube only. Add fittings (about 1 to 1.5 kg each), boards (about 20 kg per 3.9 m board) and other items for total load. For planning and estimating only. This does not replace TG20:21 compliance (a TG20 compliance sheet or eGuide output) or a scaffold design by a competent person.
Sources
- BS EN 39:2001 Loose steel tubes for tube and coupler scaffolds (48.3 mm OD, 4.0 mm wall)
- Properties of scaffold (steel tube 48.3 × 4.0 mm, 4.37 kg/m; 38 mm board 225 mm wide, 6 kg/m, 25 kg/m², 1.2 m max span; coupler safe working loads)
- NASC TG20:21 Good practice guidance for tube and fitting scaffolding (Operational Guide, Design Guide, User Guide and eGuide compliance sheets)
Results are calculations from the published methods and figures shown, and depend on the data you enter. For planning and checking only. Scaffolds must be erected to NASC TG20 or a bespoke design by competent persons, and lifting operations planned under LOLER by a competent person. Never rely on these results instead of a design, a lift plan or manufacturer ratings.