India's structural steel industry uses its own section standard — IS 808 — with designation systems that look unfamiliar to estimators trained on AISC or British standards. If you're working on Indian projects or with Indian fabricators, here's what you need to know.
What Is IS 808?
IS 808 is the Bureau of Indian Standards specification for hot rolled steel sections — beams, columns, channels, and angles. It was first established in 1957 and has been revised multiple times, with the current revision covering the section families used in modern Indian structural construction.
IS 808 is part of a broader Indian Standards (IS) framework. While IS 808 covers section dimensions and geometry, IS 2062 covers the steel material specification (equivalent to ASTM A36 or A572 in the US).
Indian sections differ from AISC and European sections in their dimensional profiles. Many are narrower in flange width relative to depth than equivalent AISC sections, which affects both structural behavior and estimating.
The IS 808 Section Families
ISMB — Indian Standard Medium Weight Beam
The ISMB series is the workhorse of Indian structural steel — equivalent in application to AISC W shapes and British Universal Beams (UB).
Designation format: ISMB [nominal depth in mm]
Common ISMB sections:
| Designation | Depth (mm) | Flange Width (mm) | Weight (kg/m) | |---|---|---|---| | ISMB 100 | 100 | 50 | 8.9 | | ISMB 150 | 150 | 75 | 14.9 | | ISMB 200 | 200 | 100 | 25.4 | | ISMB 250 | 250 | 125 | 37.3 | | ISMB 300 | 300 | 140 | 46.1 | | ISMB 400 | 400 | 140 | 61.6 | | ISMB 500 | 500 | 180 | 86.9 | | ISMB 600 | 600 | 210 | 122.6 |
Note that flange widths are relatively narrow compared to depth — ISMB 500 has a 180mm flange on a 500mm deep section, while an equivalent W18 AISC beam is more proportional.
ISLB — Indian Standard Light Weight Beam
The ISLB series is lighter and more economical, used where loads are lower. Designation: ISLB [depth in mm].
ISLB 200 (200mm deep, 100mm flange, 19.8 kg/m) through ISLB 600 (600mm deep, 210mm flange, 99.5 kg/m).
ISWB — Indian Standard Wide Flange Beam
The ISWB series is wider-flanged than ISMB, providing better resistance to lateral-torsional buckling. Used for longer spans and heavier loads.
ISWB 150 through ISWB 600. ISWB 600 weighs 145.1 kg/m — among the heaviest standard Indian beam sections.
ISHB — Indian Standard H-Beam (Column Section)
ISHB sections are designed for column use — deeper flange, more symmetrical cross-section. Equivalent in application to AISC W14 and British UC (Universal Column) sections.
| Designation | Depth (mm) | Flange Width (mm) | Weight (kg/m) | |---|---|---|---| | ISHB 150 | 150 | 150 | 34.6 | | ISHB 200 | 200 | 200 | 40.0 | | ISHB 250 | 250 | 250 | 54.7 | | ISHB 300 | 300 | 250 | 63.0 | | ISHB 400 | 400 | 250 | 82.2 |
ISMC — Indian Standard Medium Weight Channel
The ISMC series is equivalent to American Standard Channel (C shape) and British PFC. Used for purlins, secondary framing, and bracing.
Designation: ISMC [depth in mm]
| Designation | Depth (mm) | Flange Width (mm) | Weight (kg/m) | |---|---|---|---| | ISMC 75 | 75 | 40 | 5.7 | | ISMC 100 | 100 | 50 | 9.2 | | ISMC 150 | 150 | 75 | 16.4 | | ISMC 200 | 200 | 75 | 22.1 | | ISMC 250 | 250 | 82 | 30.4 | | ISMC 300 | 300 | 90 | 36.3 | | ISMC 400 | 400 | 100 | 50.1 |
ISA — Indian Standard Angle
ISA sections are equal and unequal leg angles. Designation: ISA [leg1] x [leg2] x [thickness] (all in mm).
Common equal leg angles: ISA 50x50x6, ISA 65x65x6, ISA 75x75x8, ISA 100x100x10, ISA 130x130x10.
Unequal leg angles: ISA 75x50x8, ISA 100x75x10, ISA 150x75x10.
ISA sections are widely used in truss members, bracing, and connection elements.
How IS 808 Sections Compare to AISC and BS Sections
This is where estimators get tripped up. IS, AISC, and BS sections are not interchangeable by nominal size. A section labeled ISMB 300 is not the same as a W12 (300mm ≈ 12 inches) or a 305x165 UB.
| Property | ISMB 300 | W12x50 (AISC) | 305x165x40 UB (BS) | |---|---|---|---| | Depth | 300 mm | 306 mm | 303 mm | | Flange width | 140 mm | 205 mm | 165 mm | | Weight | 46.1 kg/m | 74.4 kg/m | 40.3 kg/m |
The ISMB 300 is significantly lighter (less steel) than the W12x50 because its flange is much narrower. This is a key difference: Indian standard beams are generally less stocky in the flange than AISC sections of similar depth.
For estimators moving between standards, the right approach is always to use the actual section properties from the IS 808 tables, not to assume equivalence based on depth.
Estimating Implications for IS 808 Projects
Weight calculations use kg/m, not lb/ft
Indian projects work in metric. Piece weight = weight per meter × length in meters, result in kilograms. Divide by 1,000 for metric tonnes.
ISMB 250 at 6 meters: 37.3 kg/m × 6 m = 223.8 kg = 0.224 tonnes.
Material pricing is in INR per metric tonne
As of early 2026, structural steel (IS 2062 Grade E250) is trading approximately ₹65,000–₹75,000 per metric tonne ex-Mumbai/Delhi for standard sections. Regional variation is significant.
Section availability is different
IS 808 sections may not be stocked at the same depths as AISC. Some ISMB/ISLB variants have limited availability outside major distribution centers. Engineers designing to IS 808 typically work with sections that are readily stocked in the Indian market.
Drawing labeling conventions
Indian structural drawings typically label sections with their full IS designation: ISMB 200, ISMC 150, ISA 75x75x8. Unlike AISC drawings where you might see "W14x30" as a shorthand, Indian drawings usually use the full series name.
Multi-Standard Estimating Support
If your shop handles projects across multiple standards — or you're an international estimator covering Indian, European, and American work — keeping separate reference tables for each standard is manageable but time-consuming to maintain.
Tools like SteelFlo maintain a built-in database of IS 808 sections alongside AISC, BS/IS, AS/NZS, and EN sections — over 2,700 sections total. The AI reads IS-format labels from uploaded PDF drawings and maps them to the correct section properties automatically, which eliminates the manual lookup step.
The steel takeoffs beyond AISC post covers the multi-standard estimating landscape in more depth.
Frequently Asked Questions
What is the difference between ISMB and ISWB sections?
ISMB (Medium Weight Beam) has narrower flanges relative to depth, while ISWB (Wide Flange Beam) has broader flanges. ISWB sections provide better resistance to lateral-torsional buckling and are preferred for longer spans and heavier loads. For equivalent depth, ISWB sections are heavier (more steel) than ISMB.
How do I convert IS 808 sections to AISC equivalents for pricing?
There is no direct conversion — the sections have different geometries. The correct approach is to use the actual weight per meter for the IS section and convert to weight per foot (1 kg/m = 0.672 lb/ft) for comparison. For structural adequacy, sections should be selected based on their actual section properties, not nominal size matching.
What steel grade is used with IS 808 sections?
IS 2062 is the standard material specification for hot rolled steel in India. The most common grade is E250 (formerly Fe410), roughly equivalent to ASTM A36 with a 250 MPa yield strength. Higher grades (E300, E350, E410) are available and used in higher-stress applications.
Are IS 808 sections used outside India?
Yes, particularly in South Asia (Bangladesh, Sri Lanka, Nepal) and in projects using Indian contractors in the Middle East and Africa. If you're estimating for Indian EPC contractors working internationally, expect IS 808 section specifications even on non-Indian projects.
Where can I find the IS 808 section tables?
The official source is the Bureau of Indian Standards (BIS). IS 808 tables are also published by major Indian steel producers including Tata Steel (Tata Blue Book) and SAIL, both of which provide dimensional and section property data for all IS 808 series.