A steel beam's weight per metre is built into its Canadian name. A W200x27 weighs about 27 kg/m (26.6 kg/m exactly), and its imperial twin, the W8x18, weighs about 18 lb/ft. To get the weight of a beam, multiply that figure by the length: a 6 m W200x27 is about 160 kg, a 20 ft W8x18 about 360 lb. The chart below gives kg/m, lb/ft and the weight of 3 m, 6 m and 20 ft lengths for the W-beams used most in houses and light commercial work, plus the older S-shape I-beams.
Steel beam weight chart: W-shapes
Mass per metre is from the CISC section tables. The lb/ft figure is the nominal weight in the imperial name; the actual value is within a fraction of a pound. Weights for lengths are calculated and rounded.
| Metric | Imperial | kg/m | lb/ft | 3 m beam (kg) | 6 m beam (kg) | 20 ft beam (lb) |
|---|---|---|---|---|---|---|
| W150x22 | W6x15 | 22.5 | 15 | 68 | 135 | 300 |
| W150x30 | W6x20 | 29.8 | 20 | 89 | 179 | 400 |
| W150x37 | W6x25 | 37.2 | 25 | 112 | 223 | 500 |
| W200x22 | W8x15 | 22.5 | 15 | 68 | 135 | 300 |
| W200x27 | W8x18 | 26.6 | 18 | 80 | 160 | 360 |
| W200x31 | W8x21 | 31.2 | 21 | 94 | 187 | 420 |
| W200x36 | W8x24 | 35.9 | 24 | 108 | 215 | 480 |
| W200x46 | W8x31 | 46.2 | 31 | 139 | 277 | 620 |
| W250x22 | W10x15 | 22.4 | 15 | 67 | 134 | 300 |
| W250x25 | W10x17 | 25.3 | 17 | 76 | 152 | 340 |
| W250x28 | W10x19 | 28.5 | 19 | 86 | 171 | 380 |
| W250x33 | W10x22 | 32.9 | 22 | 99 | 197 | 440 |
| W250x39 | W10x26 | 38.5 | 26 | 116 | 231 | 520 |
| W250x45 | W10x30 | 44.7 | 30 | 134 | 268 | 600 |
| W250x58 | W10x39 | 58.2 | 39 | 175 | 349 | 780 |
| W310x24 | W12x16 | 23.9 | 16 | 72 | 143 | 320 |
| W310x28 | W12x19 | 28.2 | 19 | 85 | 169 | 380 |
| W310x33 | W12x22 | 32.8 | 22 | 98 | 197 | 440 |
| W310x39 | W12x26 | 38.8 | 26 | 116 | 233 | 520 |
| W310x45 | W12x30 | 44.5 | 30 | 134 | 267 | 600 |
| W310x52 | W12x35 | 52.2 | 35 | 157 | 313 | 700 |
| W310x60 | W12x40 | 59.7 | 40 | 179 | 358 | 800 |
| W360x33 | W14x22 | 32.9 | 22 | 99 | 197 | 440 |
| W360x39 | W14x26 | 38.9 | 26 | 117 | 233 | 520 |
| W360x45 | W14x30 | 44.8 | 30 | 134 | 269 | 600 |
| W360x57 | W14x38 | 56.8 | 38 | 170 | 341 | 760 |
| W410x46 | W16x31 | 46.2 | 31 | 139 | 277 | 620 |
| W410x54 | W16x36 | 53.7 | 36 | 161 | 322 | 720 |
| W460x52 | W18x35 | 52.2 | 35 | 157 | 313 | 700 |
| W460x60 | W18x40 | 59.7 | 40 | 179 | 358 | 800 |
| W530x66 | W21x44 | 65.9 | 44 | 198 | 395 | 880 |
| W610x82 | W24x55 | 82.4 | 55 | 247 | 494 | 1,100 |
For depth, flange width and thickness of these sections, see the Canadian W-shape size chart.
S-shape (standard I-beam) weights
S-shapes are the older "true" I-beams, with narrower, sloped flanges. They're less common in new buildings but turn up in renovations, hoist rails and older drawings. Values are from the AISC Shapes Database metric columns; Canadian tables may round the mass in the metric name.
| Metric | Imperial | kg/m | lb/ft |
|---|---|---|---|
| S75x8.5 | S3x5.7 | 8.5 | 5.7 |
| S100x11.5 | S4x7.7 | 11.5 | 7.7 |
| S130x15 | S5x10 | 15.0 | 10 |
| S150x18.6 | S6x12.5 | 18.6 | 12.5 |
| S200x27.4 | S8x18.4 | 27.4 | 18.4 |
| S250x37.8 | S10x25.4 | 37.8 | 25.4 |
| S310x47.3 | S12x31.8 | 47.3 | 31.8 |
If you're replacing or matching an old I-beam, measure the depth, flange width and flange slope; a W-shape of the same depth is a different section. Ask your supplier to confirm the section before ordering a match.
How to calculate beam weight
From the table (the normal way):
Weight (kg) = mass per metre (kg/m) x length (m)
Weight (lb) = weight per foot (lb/ft) x length (ft)
A W250x33 at 5.4 m: 32.9 x 5.4 = 178 kg.
Converting units:
- kg/m to lb/ft: divide by 1.488
- lb/ft to kg/m: multiply by 1.488
- kg to lb: multiply by 2.205
From dimensions (when you don't have a table): add the area of the two flanges and the web in square metres, multiply by the length and by the density of steel, 7,850 kg/m³. This slightly underestimates a rolled beam because it ignores the fillets where the web meets the flanges, so use the table whenever you can. Our guide on how to calculate structural steel weight works through the method for beams, plates and tubes.
Don't forget the extras. A fabricated beam weighs more than the bare section: end plates, cap and bearing plates, stiffeners and clips add weight, and copes and holes take a little away. For a basement beam with two welded plates, the extras are usually small, but on a beam with heavy connections they can add noticeably.
Why beam weight matters
Handling. Weight decides how a beam gets from the truck to its final position. A 6 m W200x27 at about 160 kg is a job for a crew with a plan; a 6 m W310x39 at about 233 kg needs lifting equipment or a well-organized team. For basement work, see how to lift a steel beam into a house without a crane. Plan the route through windows and doors before delivery day, and follow your provincial health and safety rules for lifting.
Delivery. Beams travel by truck, and length usually limits delivery more than weight on residential jobs. Long beams may need to be spliced or delivered in sections. See standard steel beam lengths and delivery limits.
Support during installation. Temporary shoring, jacks and posts have to carry the beam's own weight plus the loads it picks up, so the installer needs the beam weight to plan the work.
Estimating. Structural steel is bought and estimated largely by weight. A take-off adds up kg/m x length for every member, plus connection material.
Weight vs strength
A heavier beam isn't automatically a stronger one for your job. Depth matters more than weight: a W250x33 (32.9 kg/m) is stiffer in bending than a W200x36 (35.9 kg/m) despite weighing less, because it's deeper. The beam size for a floor or wall opening comes from the span, the loads and the supports, which is a designer's job. If you're asking how much a beam can carry rather than how much it weighs, read how much weight a steel beam can hold.
Getting beams cut, fabricated and delivered
We fabricate wide-flange beams to your drawings, with end plates, holes, connections and camber as specified, and deliver them across the GTA and Ontario, marked to match the drawings. When you ask for a quote, tell us about site access and any length limits.
Send your beam schedule or drawings for a quote, or browse our steel products, including beams, posts and plates.
Frequently asked questions
How much does a steel I-beam weigh per metre?
It's in the name. A Canadian W-beam is designated by depth and mass, so a W200x27 weighs about 27 kg/m (26.6 kg/m exactly) and a W310x39 about 39 kg/m. Common house beams weigh roughly 22 to 45 kg/m.
How much does a 20 foot steel beam weigh?
Multiply the weight per foot by 20. A W8x18 (W200x27) at 20 ft weighs about 360 lb (about 163 kg), and a W10x22 (W250x33) about 440 lb (about 200 kg), before any welded plates.
How do I convert beam weight from kg/m to lb/ft?
Divide kg/m by 1.488, or multiply lb/ft by 1.488 to get kg/m. A W250x33 at 32.9 kg/m is about 22.1 lb/ft, which is why its imperial name is W10x22.
How do you calculate the weight of an I-beam?
Look up the mass per metre in a section table and multiply by the length. If you only have the dimensions, add up the areas of the two flanges and the web, multiply by the length and by the density of steel, 7,850 kg per cubic metre.
