Steel Angle Weight Chart — ISA Equal & Unequal Angle Properties
Steel angles (L-sections) are the backbone of steel trusses, bracings, and connections. Whether you're designing a roof truss, bracing a portal frame, or connecting beams to columns — you need the weight and section properties of ISA angles. This article provides the complete reference table for all Indian Standard angles as per IS 808:2021.
Quick Formula: For an angle with legs A × B and thickness t:
Weight (kg/m) ≈ (A + B − t) × t × 0.00785
For equal angles (A = B): Weight ≈ (2A − t) × t × 0.00785
ISA Equal Angles — Weight Chart
Equal angles have both legs the same length. They're symmetric and easy to connect with gusset plates. Most commonly used in trusses and bracings.
| Section | Legs (mm) | Thickness (mm) | Weight (kg/m) | Area (cm²) | Ixx (cm⁴) | Common Use |
|---|---|---|---|---|---|---|
| ISA 20×20×3 | 20 × 20 | 3 | 0.8 | 1.06 | 0.28 | Light bracings |
| ISA 25×25×3 | 25 × 25 | 3 | 1.1 | 1.36 | 0.59 | Light bracings |
| ISA 30×30×3 | 30 × 30 | 3 | 1.4 | 1.71 | 1.1 | Bracings, cleats |
| ISA 40×40×5 | 40 × 40 | 5 | 3.0 | 3.75 | 4.2 | Light trusses |
| ISA 50×50×6 | 50 × 50 | 6 | 4.5 | 5.64 | 9.3 | Trusses, bracings |
| ISA 60×60×6 | 60 × 60 | 6 | 5.4 | 6.84 | 16.7 | Trusses, purlins |
| ISA 65×65×6 | 65 × 65 | 6 | 5.8 | 7.44 | 21.9 | Trusses, bracings |
| ISA 75×75×6 | 75 × 75 | 6 | 6.8 | 8.64 | 33.5 | Trusses, towers |
| ISA 80×80×8 | 80 × 80 | 8 | 9.6 | 12.16 | 52.4 | Trusses, towers |
| ISA 90×90×8 | 90 × 90 | 8 | 10.8 | 13.76 | 73.1 | Heavy trusses |
| ISA 100×100×10 | 100 × 100 | 10 | 14.9 | 19.0 | 123.4 | Transmission towers |
| ISA 110×110×10 | 110 × 110 | 10 | 16.5 | 21.0 | 164.2 | Transmission towers |
| ISA 130×130×10 | 130 × 130 | 10 | 19.7 | 25.0 | 259.0 | Heavy structures |
| ISA 150×150×12 | 150 × 150 | 12 | 27.2 | 34.56 | 461.3 | Heavy towers, columns |
| ISA 200×200×15 | 200 × 200 | 15 | 45.5 | 57.75 | 1198.8 | Heavy columns, towers |
ISA Unequal Angles — Weight Chart
Unequal angles have different leg lengths. The longer leg typically goes along the loaded direction. Common in stair stringers, purlin cleats, and truss connections.
| Section | Legs (mm) | Thickness (mm) | Weight (kg/m) | Area (cm²) | Ixx (cm⁴) | Iyy (cm⁴) |
|---|---|---|---|---|---|---|
| ISA 30×20×3 | 30 × 20 | 3 | 1.1 | 1.36 | 0.8 | 0.26 |
| ISA 40×25×4 | 40 × 25 | 4 | 1.9 | 2.36 | 2.5 | 0.7 |
| ISA 50×30×5 | 50 × 30 | 5 | 2.9 | 3.75 | 5.8 | 1.7 |
| ISA 60×40×5 | 60 × 40 | 5 | 3.7 | 4.75 | 12.2 | 4.1 |
| ISA 75×50×6 | 75 × 50 | 6 | 5.6 | 7.14 | 30.3 | 10.3 |
| ISA 90×60×6 | 90 × 60 | 6 | 6.8 | 8.64 | 54.3 | 19.1 |
| ISA 90×60×8 | 90 × 60 | 8 | 8.9 | 11.36 | 70.3 | 24.4 |
| ISA 100×65×8 | 100 × 65 | 8 | 9.8 | 12.56 | 105.5 | 32.4 |
| ISA 100×75×8 | 100 × 75 | 8 | 10.5 | 13.36 | 113.4 | 49.6 |
| ISA 125×75×8 | 125 × 75 | 8 | 12.1 | 15.36 | 198.3 | 49.5 |
| ISA 150×75×10 | 150 × 75 | 10 | 16.8 | 21.5 | 385.7 | 57.5 |
| ISA 150×115×10 | 150 × 115 | 10 | 19.7 | 25.5 | 433.3 | 193.3 |
| ISA 200×100×10 | 200 × 100 | 10 | 22.6 | 28.8 | 930.2 | 117.1 |
| ISA 200×150×12 | 200 × 150 | 12 | 31.6 | 40.32 | 1173.1 | 527.7 |
Equal vs Unequal — When to Use Which
- Equal angles — Truss members (both chords and diagonals), X-bracings, connection angles where both legs connect to different elements
- Unequal angles — Purlin cleats (long leg vertical for depth), stair stringers, unequal connection requirements, edge angles on plate girders
Weight Calculation Example
Roof truss with 24 members of ISA 75×75×6, average length 2.5m:
24 × 2.5m × 6.8 kg/m = 408 kg per truss
For 10 trusses at 4m spacing: 4,080 kg = 4.08 tonnes
For the full interactive table with all 37 angle sections (18 equal + 19 unequal), use the Steel Section Table.