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Steel video · 0:55

W12x26 vs W12x40: Same Depth Family, Different Beam

Compare W12x26 and W12x40 dimensions, weight, flange width, stiffness, and connection implications before treating two W12 beams as equivalent.

Practical context

How the steel information fits the project workflow

W12×26 is 12.2 inches deep; W12×40 is 11.9 inches deep.

Never substitute shapes using the W12 label or pounds per foot alone.

Companion reading and practice

What changes when nominal depth stays similar?

For a fictional 20 ft piece, nominal weight is 520 lb for W12X26 and 800 lb for W12X40. The difference is 280 lb before any added connection material.

The common W12 prefix does not make the dimensions or section properties identical. Compare the actual database records and the property units. This comparison describes geometry and nominal weight; it does not show that either member can replace the other in a structure.

Try it with a sample

Open both sections in Shape Comparison and note which dimensions differ as well as the weight.

Compare the two reference records

Examples are fictional learning exercises. This companion text adds context to the video; the transcript below records the narration.

Primary sources

References and further reading

Use the edition and requirements adopted for the project. These references support further reading; a short video does not reproduce the complete standards.

Published by Quantum Steel Design. Sources and editorial approach · Report a correction · Companion guide updated .

Accessible transcript

W12x26 vs W12x40: Same Depth Family, Different Beam transcript

The visible transcript makes the video content available to people and search systems without requiring playback.

  1. W twelve by twenty-six and W twelve by forty share a depth family, but they are very different beams.
  2. The final numbers are nominal weight: twenty-six versus forty pounds per foot.
  3. Here is the surprise. W twelve by twenty-six is twelve point two inches deep. W twelve by forty is only eleven point nine.
  4. The heavier beam is wider: eight point zero one inches versus six point four nine at the flange.
  5. Its major-axis moment of inertia is three hundred seven inches to the fourth, compared with two hundred four.
  6. That changes stiffness, strength checks, connections, clearances, handling weight, and sometimes availability.
  7. Same nominal depth does not mean the same envelope. Never substitute without comparing properties and obtaining required approval.
  8. Compare both shapes side by side at Quantum Steel Design.

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