Weight, Length, Cost & Section Properties for Equal Angle Steel — BS EN 10056-1 — 2026
Equal angle sections (also called equal leg angles, L sections, or simply angles) are one of the most widely used structural steel sections in UK construction and fabrication. They consist of two legs of equal width meeting at a right angle, manufactured by hot-rolling from steel billets to BS EN 10056-1 (dimensions) and BS EN 10025-2 (material properties). In the UK, equal angles are specified by their leg length and thickness — for example, L 100 × 100 × 10 means 100mm legs with 10mm wall thickness.
Equal angles are versatile sections used across a wide range of structural and non-structural applications: bracing and restraint members in structural steelwork, lintels over openings in brickwork and blockwork, shelf angles supporting masonry cladding, frame members in fabricated structures, gusset plates and connections, stair stringers and nosings, post caps and bases, frame corners and brackets, and numerous general fabrication and engineering applications. Their symmetric cross-section means their section properties about both principal axes (u-u and v-v) are equal, simplifying design calculations for many uses.
An equal angle (BS EN 10056-1) has two legs of equal width and thickness — for example, L 75 × 75 × 8. An unequal angle has two legs of different widths — for example, L 100 × 75 × 8. Equal angles are more common in structural applications where the section's symmetry simplifies connection detailing and the equal legs allow the section to be used in any orientation without loss of section efficiency. Unequal angles are preferred where greater depth is needed in one direction — typically as lintels or shelf angles where a longer vertical leg provides more flexural stiffness in the spanning direction.
S275 (formerly Grade 43) is the most widely used grade for equal angle sections in UK general structural applications. It has a minimum yield strength of 275 N/mm² (for thicknesses up to 16mm) and is readily available from all UK steel stockholders in the full standard size range. S275 equal angles are suitable for the vast majority of structural steelwork applications — connections, bracing, lintels, shelf angles, and general fabrication — and are the default grade specification in most UK structural drawings unless a higher grade is specifically required.
S355 (formerly Grade 50) has a minimum yield strength of 355 N/mm² — approximately 29% higher than S275. S355 equal angles are specified where higher strength allows a smaller, lighter section to be used, reducing total steel weight and cost in weight-critical applications. S355 is commonly specified in bracing members, large-span shelf angles, and structural frames where S275 would require a heavier section to satisfy utilisation criteria. The material cost per tonne of S355 is approximately 5–10% above S275.
Hot-dip galvanised (HDG) equal angles have been zinc-coated after rolling to provide corrosion protection — required for external applications, buried steelwork, marine environments, and anywhere the section will be exposed to moisture. HDG angles cost approximately 25–45% more than equivalent black (uncoated) sections due to the galvanising process cost. Stainless steel equal angles (Grade 304 and 316) are also available for highly corrosive or hygienic environments but at a significant cost premium — typically 4–8× the cost of equivalent carbon steel.
In the UK, equal angle sections are stocked in standard lengths of 6.0m and 6.1m for most commonly used sections. Larger sections (150mm and above) are often available in 9m and 12m lengths from major stockholders. The difference between 6.0m and 6.1m is a historical legacy — some European mills roll to 6.1m and some to 6.0m — but the 100mm difference is important in cut list calculations. Always confirm the stock length with your supplier before preparing a detailed cut list.
Smaller sections (25–50mm) are sometimes available in 3m lengths for retail and small trade customers from builders merchants. For project quantities of 5 tonnes or more, negotiating mill-direct or ex-mill pricing from stockholders can provide savings of 8–15% against standard trade list prices. Most UK steel stockholders carry a full range of BS EN 10056-1 equal angles in S275 black from 25 × 25 × 3 up to 200 × 200 × 24.
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| Section | Leg (mm) | Thickness t (mm) | Weight (kg/m) | Area A (cm²) | Ixx (cm⁴) | rxx (cm) | Zxx (cm³) | cv (cm) | Surface (m²/m) |
|---|---|---|---|---|---|---|---|---|---|
| L 25×25×3 | 25 | 3 | 1.12 | 1.43 | 0.80 | 0.748 | 0.44 | 0.72 | 0.095 |
| L 25×25×4 | 25 | 4 | 1.45 | 1.85 | 0.99 | 0.731 | 0.56 | 0.75 | 0.093 |
| L 30×30×3 | 30 | 3 | 1.36 | 1.74 | 1.39 | 0.894 | 0.64 | 0.83 | 0.115 |
| L 30×30×4 | 30 | 4 | 1.78 | 2.27 | 1.77 | 0.883 | 0.83 | 0.86 | 0.114 |
| L 40×40×4 | 40 | 4 | 2.42 | 3.08 | 4.47 | 1.20 | 1.55 | 1.12 | 0.154 |
| L 40×40×5 | 40 | 5 | 2.97 | 3.79 | 5.43 | 1.20 | 1.90 | 1.15 | 0.152 |
| L 40×40×6 | 40 | 6 | 3.52 | 4.48 | 6.31 | 1.19 | 2.23 | 1.18 | 0.150 |
| L 50×50×5 | 50 | 5 | 3.77 | 4.80 | 10.90 | 1.51 | 3.00 | 1.40 | 0.192 |
| L 50×50×6 | 50 | 6 | 4.47 | 5.69 | 12.80 | 1.50 | 3.56 | 1.43 | 0.190 |
| L 50×50×8 | 50 | 8 | 5.82 | 7.41 | 16.10 | 1.47 | 4.57 | 1.48 | 0.186 |
| L 60×60×5 | 60 | 5 | 4.57 | 5.82 | 19.40 | 1.83 | 4.40 | 1.64 | 0.232 |
| L 60×60×6 | 60 | 6 | 5.42 | 6.91 | 22.80 | 1.82 | 5.20 | 1.67 | 0.230 |
| L 60×60×8 | 60 | 8 | 7.09 | 9.03 | 29.00 | 1.79 | 6.74 | 1.73 | 0.227 |
| L 60×60×10 | 60 | 10 | 8.69 | 11.10 | 35.10 | 1.78 | 8.24 | 1.78 | 0.224 |
| L 70×70×6 | 70 | 6 | 6.38 | 8.13 | 37.70 | 2.15 | 7.19 | 1.92 | 0.270 |
| L 70×70×7 | 70 | 7 | 7.38 | 9.40 | 43.30 | 2.15 | 8.30 | 1.94 | 0.269 |
| L 70×70×8 | 70 | 8 | 8.36 | 10.60 | 48.70 | 2.14 | 9.40 | 1.97 | 0.267 |
| L 75×75×6 | 75 | 6 | 6.85 | 8.73 | 46.40 | 2.31 | 8.27 | 2.03 | 0.290 |
| L 75×75×8 | 75 | 8 | 8.99 | 11.40 | 59.80 | 2.29 | 10.80 | 2.08 | 0.287 |
| L 75×75×10 | 75 | 10 | 11.10 | 14.10 | 72.70 | 2.27 | 13.30 | 2.13 | 0.284 |
| L 80×80×6 | 80 | 6 | 7.34 | 9.35 | 56.60 | 2.46 | 9.35 | 2.14 | 0.310 |
| L 80×80×8 | 80 | 8 | 9.63 | 12.30 | 73.40 | 2.45 | 12.20 | 2.19 | 0.307 |
| L 80×80×10 | 80 | 10 | 11.90 | 15.10 | 89.20 | 2.43 | 15.00 | 2.24 | 0.304 |
| L 90×90×8 | 90 | 8 | 10.90 | 13.90 | 106 | 2.76 | 15.80 | 2.43 | 0.347 |
| L 90×90×10 | 90 | 10 | 13.40 | 17.10 | 130 | 2.75 | 19.50 | 2.48 | 0.344 |
| L 90×90×12 | 90 | 12 | 15.90 | 20.30 | 152 | 2.74 | 23.10 | 2.53 | 0.341 |
| L 100×100×8 | 100 | 8 | 12.20 | 15.50 | 148 | 3.09 | 19.90 | 2.67 | 0.387 |
| L 100×100×10 | 100 | 10 | 15.00 | 19.20 | 181 | 3.07 | 24.60 | 2.72 | 0.384 |
| L 100×100×12 | 100 | 12 | 17.80 | 22.70 | 214 | 3.07 | 29.30 | 2.77 | 0.381 |
| L 100×100×15 | 100 | 15 | 21.90 | 27.90 | 258 | 3.05 | 35.80 | 2.85 | 0.377 |
| L 120×120×10 | 120 | 10 | 18.20 | 23.20 | 316 | 3.69 | 35.50 | 3.22 | 0.464 |
| L 120×120×12 | 120 | 12 | 21.60 | 27.50 | 372 | 3.68 | 42.20 | 3.27 | 0.461 |
| L 120×120×15 | 120 | 15 | 26.60 | 33.90 | 452 | 3.65 | 51.80 | 3.34 | 0.457 |
| L 150×150×10 | 150 | 10 | 23.00 | 29.30 | 634 | 4.65 | 57.00 | 4.00 | 0.582 |
| L 150×150×12 | 150 | 12 | 27.30 | 34.80 | 748 | 4.63 | 67.70 | 4.05 | 0.579 |
| L 150×150×15 | 150 | 15 | 33.80 | 43.00 | 912 | 4.60 | 83.50 | 4.12 | 0.575 |
| L 150×150×18 | 150 | 18 | 40.10 | 51.10 | 1070 | 4.58 | 99.00 | 4.19 | 0.571 |
| L 200×200×16 | 200 | 16 | 48.70 | 62.00 | 2340 | 6.14 | 158 | 5.52 | 0.775 |
| L 200×200×20 | 200 | 20 | 60.30 | 76.80 | 2860 | 6.11 | 195 | 5.60 | 0.770 |
| L 200×200×24 | 200 | 24 | 71.80 | 91.50 | 3360 | 6.06 | 231 | 5.69 | 0.766 |
Section properties are for equal angles with equal legs per BS EN 10056-1:2017. Ixx = Iyy = second moment of area about axes parallel to legs through centroid. rxx = radius of gyration. Zxx = elastic section modulus. cv = distance from back of leg to centroid. Surface area in m² per metre length. Values are for guidance — always use certified section property tables for structural design calculations.
| Grade / Finish | Small sections (25–75mm) | Medium sections (80–120mm) | Large sections (150–200mm) | Notes |
|---|---|---|---|---|
| S275 Black (mill scale) | £850–£980/t | £780–£920/t | £760–£900/t | Most common — standard trade account pricing May 2026 |
| S355 Black | £890–£1,020/t | £820–£960/t | £800–£940/t | ~5–10% premium over S275. Not all sizes ex-stock |
| S275 Red Oxide Primed | £920–£1,060/t | £850–£1,000/t | £830–£980/t | ~£50–£80/t premium over black. Primed for corrosion protection |
| Hot-dip Galvanised (HDG) | £1,150–£1,380/t | £1,100–£1,320/t | £1,080–£1,300/t | ~35–45% premium over black. Required for external / buried use |
| Stainless — Grade 304 | £3,800–£4,500/t | £3,600–£4,200/t | POA | ~4–5× black steel. Not all sizes ex-stock — allow lead time |
| Stainless — Grade 316 | £4,500–£5,500/t | £4,200–£5,000/t | POA | ~5–7× black steel. Marine grade. Extended lead times typical |
Prices are indicative May 2026 UK trade account rates for cut lengths ex-stock. Small volume cash/retail prices typically 20–35% higher. Prices fluctuate with global steel market — always obtain current quotes from suppliers. Cutting, processing, and delivery charges are additional. Minimum order quantities may apply for smaller sizes.
All equal angles in the UK are manufactured to BS EN 10056-1:2017 (Specification for structural steel equal and unequal leg angles). This replaces the former BS 4848 Part 4. Section dimensions, tolerances, and geometric properties are defined in this standard. Always specify the standard when ordering to ensure correct dimensional compliance.
Equal angles are designated as L A × A × t — where A is the leg length in mm and t is the leg thickness in mm. Example: L 100 × 100 × 10 has 100mm legs and 10mm wall thickness. The root radius (fillet at the inside of the right angle) is not part of the designation but affects section properties and is specified in BS EN 10056-1.
S275 (yield strength 275 N/mm² for t ≤ 16mm, 265 N/mm² for 16 < t ≤ 40mm) is the most widely used grade for equal angle sections in UK structural applications. Available ex-stock from all major UK steel stockholders across the full BS EN 10056-1 size range. Specified to BS EN 10025-2.
The total weight of any equal angle quantity is simply: Weight (kg) = Unit weight (kg/m) × Total length (m). For example, 12 metres of L 75 × 75 × 8 at 8.99 kg/m = 12 × 8.99 = 107.9 kg. Unit weights are published in BS EN 10056-1 and are based on a steel density of 7,850 kg/m³.
Standard stock lengths in the UK are 6.0m for most sections, with 6.1m available from some mills and stockholders for the common sizes. Larger sections (150mm+) may be available in 9m or 12m. Always confirm the stock length with your supplier — the difference between 6.0m and 6.1m matters in cut list planning.
Because both legs are equal, the section is symmetric about the diagonal axis through the corner. The principal axes of inertia are the u-u axis (diagonal at 45° through the corner, maximum I) and v-v axis (also diagonal at 45° but perpendicular to u-u, minimum I). Section properties about the xx and yy axes (parallel and perpendicular to legs) are equal: Ixx = Iyy.
The centroid of an equal angle section lies on the line of symmetry (diagonal through the corner) at a distance cv from the back of the legs. For L 100 × 100 × 10, cv ≈ 27.2mm from the back face of each leg. This offset is important for calculating bending stresses and connection eccentricities in structural design.
Equal angles are widely used in UK construction as: structural bracing members, steel lintels over openings in masonry, shelf angles supporting masonry cladding, stair stringers and nosings, frame corners and brackets, gusset plates in bolted connections, secondary steelwork and purlins, and general fabrication. Their versatility and wide availability make them one of the most stocked sections in UK steel stockholders.
For external applications — exposed lintels, balcony supports, garden structures, underground brackets — hot-dip galvanising (HDG) is the standard corrosion protection. HDG adds approximately 35–45% to the cost of the steel section but provides 25–50 years of corrosion protection in typical UK environments without further maintenance.
Most UK steel stockholders charge for cutting sections to length: typically £2–£8 per cut for common sizes, rising to £8–£20 per cut for large sections or plasma/saw cutting. Minimum cutting charges and minimum order values (typically £50–£200) also apply at most stockholders. Factor these costs into your total material budget — multiple short cuts on a large order can add significantly to the total cost.
The surface area per metre is used to calculate primer, paint, and galvanising quantities. For an equal angle, the approximate surface area per metre is approximately 4 × leg width (metres) minus the corner overlap — values are tabulated in BS EN 10056-1. Example: L 100 × 100 × 10 has approximately 0.387 m²/m of paintable surface.
In structural applications, equal angles may require passive fire protection (intumescent coating, boarding, or concrete encasement) depending on the required fire resistance period and the section factor (Hp/A) of the member. The section factor is the ratio of the heated perimeter to the cross-sectional area — smaller sections have higher section factors and heat up faster. Always consult a structural engineer for fire protection design of structural angle sections.
The weight of any equal angle section is calculated as: Weight (kg) = Unit weight (kg/m) × Length (m). The unit weight (kg/m) for each BS EN 10056-1 section is tabulated in the section properties table above. For example, 15 metres of L 100 × 100 × 10 at 15.00 kg/m = 15 × 15.00 = 225 kg. For multiple pieces: multiply the weight per metre by the total length of all pieces combined. The unit weights are calculated from the section dimensions and the standard steel density of 7,850 kg/m³ — the actual weight will agree to within ±2.5% (the BS EN 10056-1 mass tolerance).
S275 and S355 are two different steel grades defined in BS EN 10025-2. S275 has a minimum yield strength of 275 N/mm² (for t ≤ 16mm) and is the standard grade for most UK structural angle applications. S355 has a minimum yield strength of 355 N/mm² — approximately 29% higher. S355 is specified when a smaller, lighter angle section will satisfy the design requirements, saving weight and sometimes cost on large orders. For most general purpose UK uses — lintels, bracing, shelf angles, brackets — S275 is perfectly adequate. S355 is specified by structural engineers for strength-critical members where weight reduction matters. The material cost per tonne of S355 is approximately 5–10% above S275, and not all sizes are available ex-stock in S355.
The correct angle size for a steel lintel depends on the span, load, and structural requirements — this is a structural engineering calculation, not a simple rule of thumb. As indicative guidance only (not to be used as a structural specification): for domestic openings up to 900mm carrying one course of brickwork only, two L 75 × 75 × 8 back-to-back (or a proprietary lintel) is commonly used. For wider openings or heavier loads, larger sections are needed. Always obtain a structural engineer's specification for lintels carrying structural loads — incorrectly specified lintels are a significant structural risk and a common cause of cracking and settlement above openings.
The cost per metre depends on the section size and the price per tonne. For S275 black equal angles in May 2026 at approximately £850/t trade: L 50 × 50 × 5 (3.77 kg/m) ≈ £3.20/m; L 75 × 75 × 8 (8.99 kg/m) ≈ £7.64/m; L 100 × 100 × 10 (15.00 kg/m) ≈ £12.75/m; L 150 × 150 × 12 (27.30 kg/m) ≈ £23.20/m. These are indicative trade prices for cut lengths — add cutting charges, delivery, and VAT to get total cost. Retail prices from builders merchants are typically 20–35% higher than trade prices. For current pricing, always obtain a quote from your steel supplier.
BS EN 10056-1:2017 (Structural steel equal and unequal leg angles — Part 1: Dimensions) is the current UK standard for equal angle section dimensions and tolerances. The material specification is covered by BS EN 10025-2:2019 (for S275, S355, S235 grades). These European standards replaced the former British Standard BS 4848 Part 4 in the early 2000s. When specifying equal angles for structural applications, quote the BS EN 10056-1 designation and the material grade to BS EN 10025-2. For example: "L 100 × 100 × 10 to BS EN 10056-1, Grade S275 JR to BS EN 10025-2".
A shelf angle is a steel equal or unequal angle section that is bolted to the face of a structural frame and projects outward to provide a support ledge for masonry cladding — particularly brick slips, natural stone cladding, and precast concrete panels. Shelf angles are required at every floor level and at the tops of tall openings in cavity wall construction to support the accumulated weight of the brick cladding above, preventing that weight from transferring to the window or door frames below. They are typically hot-dip galvanised or stainless steel (Grade 316) to resist corrosion in the cavity environment. The angle size is determined by structural calculation based on the tributary area of cladding, the span between fixings, and the deflection limits for the frame. L 100 × 100 × 12 to L 150 × 150 × 15 in stainless or galvanised steel are commonly used shelf angle sizes in UK multi-storey construction.
Equal angles can be ordered from: (1) Steel stockholders — major UK stockholders such as Steel and Tube, Barrett Steel, Rainham Steel, Metals4U, and dozens of regional operators hold ex-stock ranges of equal angles in standard lengths. Stockholders cut to your required lengths for a small cutting charge. (2) Builders merchants — Jewson, Travis Perkins, and similar hold a limited range of small angles (typically 25–75mm) in standard lengths for domestic and small trade customers. (3) Online steel suppliers — various online platforms allow ordering by length or by the piece with next-day delivery available for common sizes. For large quantities (5t+), contact a stockholder's trade desk to negotiate ex-list pricing. Always specify the section designation (e.g. L 75 × 75 × 8 to BS EN 10056-1), grade (S275 or S355), finish (black, primed, HDG), and required lengths when ordering.
The section factor is a measure of how quickly a steel section heats up in a fire — it is the ratio of the heated perimeter (Hp, in mm) to the cross-sectional area (A, in mm²). A high section factor means the section heats up quickly and requires more fire protection. For equal angles, the heated perimeter depends on how the section is exposed — a fully exposed section has a larger heated perimeter than one with one face against a wall. For L 100 × 100 × 10, the cross-sectional area is 1,920 mm², and the exposed perimeter (for a fully exposed equal angle) is approximately 380mm, giving an Hp/A of approximately 198 m⁻¹. This is relatively high compared to I-sections and H-sections of similar strength, meaning equal angles used as structural members in fire-resistance-rated construction typically require more fire protection material than equivalent heavier sections. Always consult a fire protection specialist or structural engineer for fire resistance design.
Yes, equal angle sections can be used as columns or struts in compression, but their structural efficiency as columns is lower than equivalent I-sections or hollow sections because their minimum radius of gyration (rvv — about the axis of minimum inertia, which is the v-v diagonal axis) is significantly smaller than Ixx. For an equal angle, rvv is approximately 0.196 × leg width, making equal angles relatively susceptible to lateral buckling when used as slender columns. They are commonly used as single-leg or double-angle compound struts in bracing frames, where the effective length is kept short by intermediate connections. For longer columns carrying significant compressive loads, hollow sections (SHS, CHS) or I-sections are generally more structurally efficient. Always obtain a structural engineer's specification for any compression member design.
Equal angles are most commonly connected by bolting through the outstanding leg. Standard bolt gauges for equal angles are specified in BS EN 1993-1-8 and the BCSA/SCI Green Book (Joints in Steel Construction — Simple Connections). For L 100 × 100 × 10, the standard gauge (distance from the back of the leg to the bolt centreline) is 55mm, giving the bolt hole and nut adequate clearance. For double-angle connections (two equal angles back-to-back), a packing plate fills the gap between the legs at connection points. Welded connections are also used — fillet welds along the toe and root of the angle leg are the most common weld configuration. Always use the appropriate connection design guidance (BCSA Green Book, SCI Steel Design Guides, or Eurocode 3 Part 1-8) for structural connection design.
Steel Resources 2026: Steel construction guidance at Steel Construction Info | Standards at BSI Group | UK Steel at UK Steel | Structural engineers at IStructE | BCSA at BCSA | SCI at Steel Construction Institute
© 2026 Equal Angle Calculator UK. Section properties are for guidance only — always use certified section property tables from BS EN 10056-1 for structural design calculations. Prices are indicative May 2026 trade estimates — always obtain current quotes from steel suppliers. Structural design must be carried out by a qualified structural engineer.