C-Channel Weight per Metre: Chart and Formula

The weight of a steel C-channel is written into its name. In the Canadian metric designation, the second number is the mass in kilograms per metre, so a C200x17 weighs about 17 kg/m and a C310x31 about 31 kg/m. In the imperial name the second number is pounds per foot: the same C200x17 is a C8x11.5, at 11.5 lb/ft. The chart below lists every standard size, and the sections after it show the formula and how to weigh up a whole order.

C-channel weight chart: kg/m and lb/ft

Mass values match the AISC Shapes Database metric columns, rounded, and the imperial weights are the nominal values from the imperial designations. The last column shows what a 6 m piece weighs, as a handy reference for handling and delivery. For the depth, flange and web dimensions of each size, see our C-channel size chart.

A 6 m length is used here only to make the numbers easy to compare. It is not a stock length; channel is stocked and cut in different lengths by different suppliers. For MC (miscellaneous) channel weights, see the MC table in the size chart linked above. Final design values should always come from the CISC Handbook of Steel Construction or your engineer.

The C-channel weight formula

Every steel weight calculation comes down to the same idea: mass equals volume times density. Structural steel is taken as 7,850 kg/m³. For a member of constant cross-section, that simplifies to:

Mass (kg/m) = cross-sectional area (mm²) x 0.00785

The 0.00785 is simply 7,850 kg/m³ converted to kilograms per square millimetre per metre of length.

For a standard size, take the area from a section table. A C200x17 (C8x11.5) has an area of about 2,170 mm² (3.37 in²):

2,170 x 0.00785 = 17.0 kg/m, which matches the table value of 17.1 kg/m within rounding.

Estimating the area from dimensions

If you only have the dimensions, you can estimate the area of a channel as one web plus two flanges:

Area ≈ (depth x web thickness) + 2 x (flange width minus web thickness) x average flange thickness

For the C200x17: depth 203 mm, web 5.6 mm, flange width 57.4 mm, average flange thickness about 9.9 mm.

• Web: 203 x 5.6 = 1,137 mm²
• Flanges: 2 x (57.4 minus 5.6) x 9.9 = 1,026 mm²
• Total: about 2,163 mm², or 2,163 x 0.00785 = 17.0 kg/m

Standard C-channels have sloped inside flange faces and rounded fillets, so this shortcut is an approximation. It lands within a few percent for the standard sizes, which is fine for estimating. For anything that matters (design, invoicing, lifting plans) use the published mass.

Cold-formed channels are different

Light channels bent from sheet or strip (steel studs, track, some purlins) are not in the chart above. Their weight is roughly the thickness times the developed width (the total length of the flattened profile) times 0.00785:

Mass (kg/m) ≈ thickness (mm) x developed width (mm) x 0.00785

A cold-formed C of the same outside size as a hot-rolled channel weighs, and carries, much less. The two are not interchangeable.

Converting between kg/m and lb/ft

Canadian drawings use kg/m, while many supplier lists, US drawings and older Canadian drawings use lb/ft. The conversions:

• kg/m x 0.672 = lb/ft
• lb/ft x 1.488 = kg/m
• 1 tonne = 1,000 kg = about 2,205 lb

Check: a C250x30 at 30.0 kg/m x 0.672 = 20.2 lb/ft, and its imperial name is C10x20. The small difference is rounding in the metric name.

How to calculate the weight of a channel order

Weighing up an order is a three-step job:

1. List every piece with its size and cut length.
2. Multiply each length (m) by the mass (kg/m) from the chart.
3. Add any plates, clips or stiffeners welded to the channel, and add everything up.

Example: channel framing for a small platform

The same in imperial: 20 ft of C10x20 is 20 x 20 = 400 lb.

A few practical notes for the arithmetic:

• Holes and copes take a little away, welded plates and clips add a little back. For estimating, most people ignore holes and add plates separately. Our guide on how to calculate structural steel weight shows how to weigh plates and other shapes.
• Rolled sections have a mass tolerance. Actual weight can differ slightly from the table, so a scale ticket will rarely match the calculation exactly.
• Primer adds very little weight; galvanizing adds more. If weight is critical, ask the coater.

Weight is not the same as strength

It is tempting to assume that a heavier channel of the same depth is proportionally stronger. It isn't quite that simple. Within one depth, the extra mass goes mostly into a thicker web, and the web adds less bending stiffness than the same steel would in the flanges. A C250x45 weighs almost twice as much as a C250x23 but is not twice as stiff in bending.

Channels also tend to twist when loaded through the web, because the shear centre sits outside the web. That is why the right channel for a job comes from the engineer's design and load tables, not from the weight chart. If you are wondering how much load a particular channel can carry, see our explainer on C-channel load capacity.

Weight does matter for practical reasons, though:

• Pricing and quoting. Steel material is commonly bought and estimated by weight, then fabrication is added on top.
• Handling. A 6 m C380x74 is over 440 kg. That is a job for lifting equipment, not hands.
• Delivery. Total weight and the longest piece decide what truck is needed.
• Dead load. The weight of the steel itself is part of the load the structure carries.

Getting channel cut and fabricated

If you have a list of channels to price, send it with sizes and lengths, or send the drawings and we'll do the take-off. We supply C-channels cut to length and fabricated with holes, copes and welded plates, along with the beams, posts and plates they connect to, and deliver across the GTA and Ontario.

Request a quote or see our steel products, including channels, beams and plates. If you are still choosing a supplier, our guide on where to buy C-channel in Ontario explains the options.