S18X70 Dimensions & Weight

S18X70 is an AISC American Standard (S) beam with an actual depth of 18 in and a 6.3 in flange, weighing 70 lb per foot — commonly used for floor beams and roof framing. It is the heaviest of the 2 S18 sizes listed here.

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S18X70 Dimensions

Property	Imperial	Metric
Depth (d)	18 in	457.2 mm
Flange width (bf)	6.25 in	158.8 mm
Cross-section area (A)	20.6 in²	132.9 cm²
Weight	70 lb/ft	104.2 kg/m

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

What does S18X70 weigh and cost?

S18X70 weighs 70 lb per foot. At an example material price of $0.92/lb that is about $64.40 per foot. Set your quantity, length, and price to total your own run:

QtyLength (ft)$ / lb

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Total weight

1,400 lbs

Material cost

$1,288.00

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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