------ | ------------- | ---------------- | ------------ | | G–L2 | 254×254 UC 73 | 4 × 4.0 | 1,170 | | L2–L4 | 203×203 UC 46 | 4 × 4.0 | 738 | | L4–R | 152×152 UC 23 | 4 × 4.0 | 368 | | Total | | | 2,276 kg |

Add splice plate and base plate weight (~8% of column mass): total order ~2,460 kg.

Worked Example 3 — Mixed Framing Lot

Problem: A single-storey portal frame (UK practice) uses: 2 × 8.5 m 457×191 UB 67 columns, 1 × 14.2 m 406×178 UB 54 rafter (per portal), and 18 × 6.0 m 200×100 PFC 23.4 purlins. Two identical portal frames.

Solution:

Columns (2 portals × 2 columns):

• 4 × 8.5 m × 67.1 kg/m = 2,281 kg

Rafters (2 portals × 1 rafter):

• 2 × 14.2 m × 54.1 kg/m = 1,536 kg

Purlins:

• 18 × 6.0 m × 23.4 kg/m = 2,527 kg

Total: 6,344 kg (6.34 tonnes). Add 4% for connections and bracing: ~6.6 tonnes order quantity.

Mass Tolerances — BS 4-1 / EN 10034

BS 4-1 (and its successor BS EN 10034) specifies a mass tolerance of ±4% for rolled sections. For UK projects:

• Use the nominal mass from the BS 4-1 section table for preliminary take-offs
• For crane lift planning within existing buildings (city-centre sites with restricted access), use the upper bound (+4%) to verify the crane capacity is adequate
• For transport, the nominal mass is sufficient — UK road haulage rates are typically priced per-tonne within standard weight bands

Estimating Connection Weight — UK Practice

Connection weight as a percentage of main member mass, based on UK steelwork contractor data (BCSA Guide):

For a 50-tonne steel frame with predominantly flexible end plate connections, allow approximately 3 tonnes for connection material in the overall take-off.

UK Hollow Section Weight — SHS, RHS, CHS

Hot-finished hollow sections to BS EN 10210 are the standard choice for UK bracing members, truss chords, and secondary framing. Cold-formed sections to BS EN 10219 are typically lighter (thinner walls at the same external dimensions) and used for purlins and cladding rails.

Common UK hollow section masses (hot-finished, S355J2H):

Cold-formed vs hot-finished weight: A cold-formed SHS 100×100×4 (BS EN 10219) weighs 11.9 kg/m, while the nearest hot-finished SHS 100×100×5 (BS EN 10210) weighs 14.8 kg/m — a 24% difference. Always confirm which standard applies before ordering. UK steelwork contractors default to hot-finished for primary structural elements and cold-formed for secondary members unless the specification says otherwise.

Steel Tonnage Benchmarks — UK Construction

Quick-reference estimates for preliminary budgeting (includes main members, connections, secondary steel, and bracing):

Note: kg/m² is Gross Internal Floor Area (GIFA). Values include connections, bracing, and secondary steel (purlins, side rails, edge beams). UK city-centre sites typically fall in the upper range due to tighter grids, vibration criteria, and more complex connections for restricted access. Add 8–12% for architecturally exposed structural steel (AESS) where members are visually expressed.

UK steel cost context: UK structural steelwork rates as of 2026 typically range from £2,400 to £3,200 per tonne (supply, fabricate, deliver, and erect), depending on complexity and location. A 100-tonne frame at £2,800/t = £280,000 for the steel package. The steel weight calculator provides the first number in that chain — accurate take-off mass — which drives procurement, logistics, and commercial negotiations.

Comparison: UK Sections vs European Sections

UK UB sections (BS 4-1) and European IPE sections (EN 10365) serve similar roles but have different dimensional families. Key differences:

• UB vs IPE: UB sections have wider flanges relative to their depth. A 406×178 UB 54 (177 mm flange) has a wider flange than an IPE 400 (180 mm flange at 400 mm depth). UB sections generally offer higher weak-axis stiffness.
• UC vs HEA/HEB: UC sections are approximately equivalent to HEB sections — both are column-weight sections. A 254×254 UC 73 (254 mm square) is similar in proportions to an HEB 260.
• Mass designation: UK UB/UC use mass in kg/m (UB 92 = 92.1 kg/m). European IPE/HEA use nominal depth (IPE 400 = ~400 mm deep with mass varying by section type).

Always use the correct regional database. The UK calculator uses BS 4-1 data; the European calculator uses EN 10365 data. Do not substitute one for the other.

Related Resources

• UK Steel Beam Sizes — BS 4-1
• UK UB/UC Section Properties
• UK Steel Design Guide — EN 1993 + UK NA
• UK Steel Grades — EN 10025 S275, S355
• Beam Capacity Calculator — EN 1993 + UK NA
• Column Capacity Calculator — EN 1993 + UK NA

FAQ

What density does the calculator use? Standard steel density of 7850 kg/m³ (7.85 t/m³) — consistent with BS 4-1, BS EN 10025, and EN 1993-1-1. This is the accepted value for structural carbon steel. Stainless steel (EN 10088) at ~8000 kg/m³ is not covered.

Are UK UB/UC sections the same as Australian UB/UC sections? They are the same series — Australian UB/UC sections are derived from the British standards. However, the specific section range differs between markets. Some UK sections (particularly the larger UC sizes) may have slight dimensional differences from their Australian counterparts. The calculator maintains separate databases for each region.

Can I calculate the weight of hollow sections? Yes. The calculator supports SHS (Square Hollow Section), RHS (Rectangular Hollow Section), and CHS (Circular Hollow Section) per BS EN 10210 (hot-finished) and BS EN 10219 (cold-formed). Hot-finished sections have slightly thinner walls and lower mass per metre compared to cold-formed sections of the same external dimensions.

Does the calculator include galvanising weight? No. Hot-dip galvanising to BS EN ISO 1461 adds approximately 3–7% to the section weight depending on section size and coating thickness. For galvanised steelwork, multiply the calculator output by 1.05 as an approximation. For precise coating masses, refer to BS EN ISO 1461 Table 1.

How accurate is this for CE marking and UKCA marking compliance? The calculator uses nominal dimensions and density — it is a design-stage estimation tool, not a weighing certificate. For CE/UKCA marked steel, the actual delivered mass is confirmed by the mill certificate (EN 10204 Type 3.1). The nominal mass from BS 4-1 is within ±4% of the actual mass for standard rolled sections.

What waste factor should I apply? Standard UK practice per BCSA guidelines: 5% for simple beam-and-column frames with shear connections; 8% for braced frames with gusset plates; 10–15% for complex connections with profiled stiffeners. These factors cover both fabrication waste (beam-ends, cut-offs) and the nominal-to-actual mass tolerance.

Design Resources

• W-Shape and HSS Section Finder — Compare with similar sections
• Steel Beam Sizes Reference — Standard beam dimensions
• EN 1993 Load Combinations — UK NA — Factored design loads

Educational reference only. Steel weight estimates are preliminary. Verify section masses against the current BS 4-1 / BS EN 10034 standards and mill certificates before procurement. Results are PRELIMINARY — NOT FOR CONSTRUCTION.