S12X40.8 Dimensions & Weight

S12X40.8 is an AISC American Standard (S) beam with an actual depth of 12 in and a 5.3 in flange, weighing 40.8 lb per foot — commonly used for light floor framing, mezzanines, and residential beams.

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S12X40.8 Dimensions

Property	Imperial	Metric
Depth (d)	12 in	304.8 mm
Flange width (bf)	5.25 in	133.4 mm
Cross-section area (A)	12 in²	77.4 cm²
Weight	40.8 lb/ft	60.7 kg/m

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

What does S12X40.8 weigh and cost?

S12X40.8 weighs 40.8 lb per foot. At an example material price of $0.92/lb that is about $37.54 per foot. Set your quantity, length, and price to total your own run:

QtyLength (ft)$ / lb

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Total weight

816 lbs

Material cost

$750.72

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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