Types of Structural Steel Shapes: W-Shapes, HSS, Channels, and Angles Explained (Canadian Designations)

“W310x97” looks like a part number. It’s actually a tiny sentence: a wide-flange beam, about 310 millimetres deep, weighing 97 kilograms per metre. Once you can read it, steel drawings stop looking like code and start looking like a plan. That’s what this guide is for.

Walk through any industrial steel building and you’ll see the same handful of shapes doing different jobs. Beams carry floors, tubes brace frames, channels tie things together, and angles hold the awkward corners. The types of structural steel shapes you choose affect strength, cost, fabrication time, and even how long the steel lasts outdoors. Here’s what each one is, where it’s used, and how Canadian sizes are written, since most of what’s online is based on imperial, American sizes.

What Are the Types of Structural Steel Shapes?

Structural steel shapes are standard cross-sections, rolled or fabricated from steel, used to build the frame of a structure. In Canada, most are produced to the CSA G40.20 and G40.21 standards, which set the general requirements and the grades. We cover the grades themselves in our guide to structural steel grades.

The main types you’ll meet on industrial projects are:

• W-shapes (wide-flange beams) for beams and columns
• HSS (hollow structural sections) in square, rectangular, and round forms
• Channels (C and MC shapes)
• Angles (L-shapes)
• Tees (WT-shapes), plates, and bars

How to Read Canadian Steel Beam Sizes

Canadian designations use metric units, and they follow a simple pattern: a letter for the shape, then dimensions in millimetres. These examples are illustrative:

• W310x97: wide-flange shape, about 310 mm deep, 97 kg per metre
• HSS 152x152x9.5: square tube, 152 mm by 152 mm, with a 9.5 mm wall
• C250x30: channel, 250 mm deep, 30 kg per metre
• L102x102x9.5: equal-leg angle, 102 mm legs, 9.5 mm thick

The mass per metre matters because steel is sold and shipped by weight, so it feeds directly into cost. That’s one reason steel beam sizes show up in our breakdown of structural steel cost factors. It’s also why most American tables are hard to use here: they list depth in inches and weight in pounds per foot.

W-Shapes: The Workhorse of Structural Steel

When people say “I-beam,” they usually mean a W-shape. It has two parallel flanges joined by a web, and that shape carries bending loads efficiently. W-shapes are the default choice for beams and columns because they’re strong for their weight and easy to connect with bolts or welds.

You’ll also hear about two relatives. S-shapes, the older American standard I-beams, have sloped inner flanges and are used less often today. WWF shapes are welded wide-flange sections built from plate, which are common in Canada when a project needs a size or strength that rolled shapes can’t supply.

On industrial sites, W-shapes show up as floor beams, crane runway girders, conveyor gallery frames, and the primary members of a mezzanine. They also support metal decking on roofs and elevated floors.

HSS: Square, Rectangular, and Round Tubes

HSS, or hollow structural sections, are closed tubes in square, rectangular, or round form. Because they’re closed, they resist twisting and handle loads from several directions well. That makes them a strong choice for columns, bracing, trusses, and handrails.

HSS also looks clean, which is why architects specify it where steel is left exposed. But it comes with trade-offs worth knowing:

• Connections are harder. Tubes need careful cutting and welding access, so fabrication time per tonne is usually higher than for W-shapes. Weld quality matters here, and our post on weld defects explains what inspectors look for.
• Coating needs planning. A closed section can’t be checked or recoated on the inside, and if it’s hot-dip galvanized it needs vent holes so zinc and air can move. See our guide to industrial coatings for how that decision is made.

Canadian HSS is also produced in different classes under CSA G40.20, so confirm the specification on your drawings.

Channels: C-Shapes and MC-Shapes

A channel is shaped like a squared-off “C,” with a web and two flanges on one side. Canadian C-shapes are the standard channel sizes, and MC-shapes cover miscellaneous channel sizes that don’t fit the standard series.

Channels are rarely the main load-carrying beam. They’re used for secondary members: purlins and girts that support roofing and wall cladding, edge beams, stair stringers, and framing for equipment and platforms. Their flat back also makes them easy to mount to other members.

Angles and Tees: The Connectors

An angle, or L-shape, has two legs meeting at a right angle, either equal or unequal in length. Angles are the connectors of the steel world: bracing, truss members, lintels, supports, and clip angles for beam connections.

A WT-shape is a structural tee, made by cutting a W-shape in half lengthwise. You’ll see tees as truss chords and in some gusset applications. Plates and bars round out the list. They’re used for base plates, stiffeners, and any part that needs to be cut to a custom shape.

How the Types of Structural Steel Shapes Compare

Treat this as a rough guide only. The right shape for a member comes from engineering calculations, not a table.

Choosing Between Types of Structural Steel Shapes on an Industrial Project

On a real project, the structural engineer chooses the shapes. They calculate the loads and set the members. The fabricator then details, cuts, welds, coats, and ships them, and the shape choices affect that work in several ways:

• Fabrication effort. Tubes and built-up sections take more time than simple beams.
• Cost. Total weight, fabrication hours, and coating all drive price.
• Corrosion exposure. Open shapes are easier to inspect and recoat than closed ones.
• Erection. Heavier members need bigger lifts, which affects crane and rigging plans.

Clear shop drawings list each member by designation, which is why the shape names matter long after the design stage. The ironworkers who set these shapes, a trade described by Red Seal’s ironworker trade description, rely on those marks to put each piece in the right place. Our overview of steel erection safety covers how that work is done safely, and our post on what ironworkers do goes deeper on the trade.

If a shape in an existing structure is damaged or corroded, the repair-or-replace question comes up, which we cover in structural steel repair vs. replacement.

Frequently Asked Questions About Types of Structural Steel Shapes

What are the main types of structural steel shapes?

The main types are W-shapes, HSS (hollow structural sections), channels, angles, tees, plates, and bars. W-shapes are the most common for beams and columns.

What does W310x97 mean?

It describes a wide-flange beam about 310 mm deep that weighs 97 kg per metre. Canadian designations list the shape letter, the nominal depth in millimetres, and the mass per metre.

What is the difference between an I-beam and a W-shape?

A W-shape has parallel flange faces, while a standard I-beam (S-shape) has sloped inner flanges. People often use “I-beam” to mean a W-shape, but the sections are different.

When is HSS better than a W-shape?

HSS is often chosen for columns, bracing, and trusses, and where steel is left exposed, because it resists twisting well. W-shapes are usually easier and cheaper to connect.

Who decides which steel shape to use?

The structural engineer selects the shapes based on the loads and design requirements. The fabricator details and builds them from the approved drawings.

Know the Shapes, Read the Drawings

Once you know the types of structural steel shapes, you can read a drawing, question a quote, and understand why one frame costs more than another. That’s the difference between receiving steel and understanding it.

Credence Construction details, fabricates, and erects all of these shapes across the mining, agricultural, and industrial sites we work on in Saskatchewan, Alberta, Manitoba, and Western Ontario. Our steel fabrication team works from drafting through erection. If you’re planning a steel project and want shapes that suit it, call us at 306-786-7000.