S8X18.4 Dimensions & Weight

S8X18.4 is an AISC American Standard (S) beam with an actual depth of 8 in and a 4 in flange, weighing 18.4 lb per foot — commonly used for lintels, trimmers, and light framing. It is the lightest of the 2 S8 sizes listed here.

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S8X18.4 Dimensions

Property	Imperial	Metric
Depth (d)	8 in	203.2 mm
Flange width (bf)	4 in	101.6 mm
Cross-section area (A)	5.41 in²	34.9 cm²
Weight	18.4 lb/ft	27.4 kg/m

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

What does S8X18.4 weigh and cost?

S8X18.4 weighs 18.4 lb per foot. At an example material price of $0.92/lb that is about $16.93 per foot. Set your quantity, length, and price to total your own run:

QtyLength (ft)$ / lb

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Total weight

368 lbs

Material cost

$338.56

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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