S15X42.9 Dimensions & Weight

S15X42.9 is an AISC American Standard (S) beam with an actual depth of 15 in and a 5.5 in flange, weighing 42.9 lb per foot — commonly used for floor beams and roof framing. It is the lightest of the 2 S15 sizes listed here.

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S15X42.9 Dimensions

Property	Imperial	Metric
Depth (d)	15 in	381 mm
Flange width (bf)	5.5 in	139.7 mm
Cross-section area (A)	12.6 in²	81.3 cm²
Weight	42.9 lb/ft	63.8 kg/m

Standard: AISC. Values from the published section tables; dimensions not listed here are not shown rather than estimated.

What does S15X42.9 weigh and cost?

S15X42.9 weighs 42.9 lb per foot. At an example material price of $0.92/lb that is about $39.47 per foot. Set your quantity, length, and price to total your own run:

QtyLength (ft)$ / lb

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Total weight

858 lbs

Material cost

$789.36

Material only, example pricing. Actual steel pricing varies by region, grade, quantity, and market conditions — use your own supplier numbers for real bids.

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