Structural steel beams and columns: types, sizes and applications
08 Sept 2026
Table of contents
- Beams and columns: the basics
- Beam types: I-beam (ISMB) vs H-beam
- Columns and built-up sections
- Sizes and section designations
- Applications in steel buildings and PEB
- Selecting beams and columns
- Price factors and sourcing
- Conclusion
- FAQs
Specifying the right rolled section for a steel frame involves more than selecting a size from a chart. Fabricators and contractors frequently encounter mismatches between engineering drawings, mill certificates, and procurement descriptions because the section family, grade, or designation system was not clearly aligned from the start.
Understanding how structural steel beams and columns differ by geometry, how Indian Standard designations work, and what drives cost helps close that gap. This article covers core section types, sizing conventions, practical applications, and sourcing considerations for Indian construction projects.
Specifications are referenced against IS 2062:2011; buyers should confirm current grade requirements against IS 2062 (Part 1):2025, available from the Bureau of Indian Standards.
Beams and columns: the basics
A beam is a horizontal load-bearing member designed to resist bending and shear from floors, roofs, equipment, or crane loads. A column is a vertical member that transfers compressive forces, and sometimes combined axial and bending effects, down to the foundations.
The distinction is functional rather than physical: the same rolled steel section can serve as a beam or a column depending on its orientation, bracing arrangement, end restraints, and the specific load case acting on it.
Column design places particular emphasis on stability against buckling, because a compression member can fail through lateral instability well before the material itself crushes. Beam design, by contrast, centres on bending capacity, shear resistance, deflection limits, and lateral restraint.
For a closer look at how these roles differ in practice, see our breakdown of the difference between steel beams and columns.
Beam types: I-beam (ISMB) vs H-beam
ISMB sections and H-beams (also called wide-flange or parallel-flange sections) are distinct section categories, both now governed by a single Indian Standard. IS 808:2021 (Fourth Revision) covers dimensions and properties for hot-rolled beam, column, channel, and angle sections, including parallel-flange sections. It supersedes both the earlier IS 808:1989 and the separate parallel-flange standard, IS 12778:2004, which older drawings and datasheets may still reference.
What is an I-beam and where is it used in construction? An I-beam is a rolled I-section used primarily as a bending member in building floors, roofs, mezzanine platforms, industrial sheds, and general steel structures where loading acts about the strong axis. Read more on how I-beams work in construction for a fuller look at the shape and its use.
Flange geometry is the critical differentiator. Flange width, flange thickness, web depth, and web thickness collectively determine bending resistance, buckling behaviour, and how easily bolted or welded connections can be detailed. Parallel-flange sections are often preferred where connection detailing and column-axis stability benefit from wider, more uniform flanges. Selecting one family over the other without checking section properties and connection requirements introduces risk.
Columns and built-up sections
Standard rolled sections can function as structural columns when the design accounts for axial load, bending, slenderness ratio, buckling about both axes, and connection forces. IS 808:2021 provides the dimensions and section properties needed for this, covering both standard and parallel-flange sections.
When a single rolled section cannot meet the required area, stiffness, or connection geometry, fabricators create built-up or compound columns from plates and rolled sections. The role of steel columns in increasing load-bearing capacity in PEB structures depends significantly on this design flexibility. However, column capacity is never a catalogue property alone. It depends on member length, end conditions, bracing, eccentricity, load combination, steel grade, and fabrication tolerances, all verified through engineer-approved design to IS 800:2007.
Sizes and section designations
Procurement and design in India rely on a shared specification system: one that aligns section family, nominal depth, flange and web dimensions, sectional mass, and section properties under a single governing standard. IS 808:2021 covers all of this across beam, column, channel, angle, and parallel-flange categories.
The table below summarises what each specification item controls in procurement and design:
| Specification item | Role in procurement and design |
| Section family | Distinguishes ISMB, column, channel, angle, and parallel-flange categories |
| Nominal depth | Primary size identifier in the section designation |
| Flange width and thickness | Governs bending resistance, local buckling, connection space, and column stability |
| Web depth and thickness | Controls shear capacity, web buckling, and connection detailing |
| Sectional mass | Basis for weight-based pricing, transport planning, and fabrication costing |
| Section properties | Provides area, moment of inertia, radius of gyration, and section modulus for design |
An H-beam size chart, whether sourced online or from a manufacturer catalogue, should be read as a standards-based property table rather than a design recommendation. The correct size for any project still depends on loads, span, unbraced length, connection forces, steel grade, and code compliance.
You can browse available beam and column sections to compare designations before finalising your specification.
Applications in steel buildings and PEB
Structural beams and columns form the primary framework of multi-storey steel buildings, industrial sheds, PEB structures, mezzanine floors, pipe racks, roof trusses, and platforms. Steel-frame buildings rely on these members because they offer predictable load paths, can be fabricated in controlled workshop conditions, and allow efficient bolted or welded assembly on site. Understanding the structural loads that affect steel frame buildings is essential before specifying any section.
Which steel grade suits a PEB or an industrial shed? The answer is always use-case-dependent. IS 2062:2011 lists structural steel grades including E250, E300, E350, E410, and E450. For PEB applications, the project engineer specifies the grade based on span, wind and seismic loads, crane requirements, corrosion exposure, and fabrication route. For industrial sheds, E250 or E350 may commonly appear, but the correct choice depends on design loads, weldability, and connection detailing. A helpful starting point for shed and factory projects is this overview of PEB industrial shed and factory building basics.
Bridge steelwork carries additional fatigue, durability, and authority-approval requirements and should be treated separately from building or shed selection.
Selecting beams and columns
Choosing the right section involves evaluating span, load case, steel grade, section family, unbraced length, deflection limits, buckling mode, connection type, fabrication method, transport constraints, and the governing design code. IS 800:2007 provides the design framework for steel construction in India, while IS 808:2021 supplies the section data that feeds into those calculations.
PEB projects typically favour optimised built-up tapered members with bolted erection and factory fabrication. Conventional construction more often relies on standard rolled sections such as ISMB beams, channels, and plates.
When should you use ISMB, ISMC, or ISA sections?
ISMB sections are typically specified for primary bending members such as beams and girders. ISMC channels serve secondary framing, edge members, lintels, and built-up combinations. ISA angles are common in bracing, trusses, cleats, and connection components. However, the final choice is always design-dependent: section properties, connection eccentricity, buckling length, and weld or bolt detailing all influence suitability. A blanket ranking of one section family over another has no engineering basis.
Price factors and sourcing
Structural steel pricing in India is typically split into two components: material cost and fabrication or erection cost. Material quotations are weight-based because section mass and total ordered tonnage determine the steel quantity. Fabrication cost accounts for cutting, welding, drilling, surface preparation, coating or painting, inspection, documentation, transport, and site erection.
What is the current structural steel fabrication cost per tonne in India?
There is no single fixed rate. The cost varies with base steel price, grade, section weight, cutting and welding complexity, coating system, inspection level, order volume, freight distance, and project location. When comparing per-tonne quotations, confirm whether the rate covers labour only, material plus fabrication, coating, transport, GST, or erection. For a detailed breakdown of these components, refer to this guide on estimating structural steel fabrication cost.
Can you buy ISMB beams and structural steel sections online?
The platform lists structural beams, columns, angles, and channels as a sourcing category, where contractors can review available sections and request a quotation. Stock availability, delivery timelines, and final pricing depend on the current quotation for your order.
Conclusion
Sourcing structural beams and columns effectively requires clarity at three levels: the relevant Indian Standard identifies dimensions and properties, the structural design confirms whether that section is adequate for the loads and spans involved, and procurement aligns grade, length, mass, certification, fabrication scope, and delivery route. For project-specific capacity decisions, always consult a qualified structural engineer and request current mill-test certificates.
Browse structural steel beams and columns on JSW One MSME
Key takeaways
A beam resists bending and shear horizontally; a column resists vertical compression. The same rolled section can serve either role depending on orientation and load path.
ISMB sections have tapered flanges; H-beams (parallel-flange sections) have uniform flanges. Both are governed by IS 808:2021. They are not interchangeable without checking section properties and connection detailing.
IS 808:2021 is the single governing standard for dimensions and section properties across beam, column, channel, angle, and parallel-flange categories.
Structural steel grades (E250, E300, E350, E410, E450) are specified under IS 2062:2011. Grade selection for any project is engineer-determined based on span, loads, and fabrication route; there is no universal correct answer.
Column capacity is never a catalogue figure. It depends on member length, end conditions, bracing, eccentricity, and load combination, verified through design to IS 800:2007.
Structural steel pricing has two components: weight-based material cost and fabrication cost. Per-tonne quotations must specify what is included — labour, material, coating, transport, GST, and erection scope all vary.
FAQs
1. What is the difference between a beam and a column?
A beam carries transverse loads through bending and shear horizontally. A column resists vertical compression and may carry bending from frame action. The same section can serve either role depending on orientation and load path.
2. What is the difference between an I-beam and an H-beam?
Both are rolled steel sections defined under IS 808:2021. An ISMB I-section has tapered flanges, while an H-beam has parallel flanges, giving different connection detailing and stability characteristics. Neither is universally interchangeable with the other.
3. What is an I-beam used for in construction?
I-beams serve as floor beams, roof members, mezzanine supports, and industrial framing where loading produces strong-axis bending. Corrosion protection must be specified separately for exposed or outdoor environments.
4. What are standard ISMB beam sizes?
Sizes are defined by IS 808:2021 through designation, nominal depth, flange and web dimensions, and sectional mass. Always specify the standard year, grade, and required length rather than relying on generic online charts.
5. Which steel is best for a pre-engineered building?
No single grade is universally correct. IS 2062:2011 grades such as E250, E350, or E450 may be specified depending on span, wind and seismic loads, crane requirements, and fabrication route, all confirmed by the project engineer.
6. How is structural steel fabrication cost calculated?
Cost builds from material weight, grade, cutting, welding, drilling, coating, inspection, freight, erection, and project location. Per-tonne rates should state whether they include material, labour, coating, transport, GST, and erection scope.
7. How do I choose a beam size for my project?
Calculate span, load, deflection limit, lateral restraint, and connection forces, then match results to IS 808:2021 section data. Structural sizing is safety-critical and requires engineer sign-off before procurement.
8. Can I order ISMB beams online in bulk?
The platform provides an online sourcing route with selectable beam attributes and quantity entry in MT. Stock availability, delivery timeline, and final pricing are confirmed through the quotation process for each order.