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W 12X87 vs HP 12X89

W 12X87 is an W section from the American AISC Shapes Database; HP 12X89 is the closest equivalent in the American AISC Shapes Database. W 12X87 carries more bending: 2163.1 cm³ of plastic modulus against 2081.2 cm³, 3.9% more. W 12X87 is the lighter of the two at 129.5 kg/m against 132.4 kg/m, a saving of 2.2% on steel weight. Both are about 316 mm deep, so either fits the same construction zone.

Section properties side by side. Bold marks the more favourable value where one is.
PropertyW 12X87
W
HP 12X89
HP
Difference
Mass129.5 kg/m132.4 kg/m-2.2%
Depth317.5 mm315 mm+0.8%
Width307.3 mm312.4 mm-1.6%
Web thickness13.1 mm18.3 mm-28.4%
Flange thickness20.6 mm18.3 mm+12.6%
Area165.2 cm²167.1 cm²-1.1%
Second moment, major (Iy)30,801 cm⁴28,845 cm⁴+6.8%
Plastic modulus, major (Wpl,y)2,163.1 cm³2,081.2 cm³+3.9%
Elastic modulus, major (Wel,y)1,933.7 cm³1,835.4 cm³+5.4%
Second moment, minor (Iz)10,031 cm⁴9,324 cm⁴+7.6%
Plastic modulus, minor (Wpl,z)989.78 cm³917.68 cm³+7.9%
Radius of gyration, minor (iz)7.8 cm7.47 cm+4.4%
Torsion constant (It)212.3 cm⁴204.8 cm⁴+3.7%

W 12X87 to AISC Shapes Database v16.0; HP 12X89 to AISC Shapes Database v16.0. Difference is expressed relative to HP 12X89.

How to choose between them

On stiffness, W 12X87 has the larger second moment of area: 30,801 cm⁴ against 28,845 cm⁴, a difference of 6.8%. This matters more often than the strength comparison, because on normal floor spans deflection rather than bending capacity sets the beam size - so if the two are close on modulus but apart on inertia, the stiffer one is usually the better answer even when it is not the stronger one.

Measured as bending capacity per kilogram of steel, W 12X87 is the more efficient section: 16.7 against 15.7 cm³ per kg/m, 6.3% better. Over a floor of repeated beams that difference is real tonnage, though it is often outweighed by whichever section the fabricator can actually source.

In short, W 12X87 is the stronger section and W 12X87 is the lighter one; where those are the same section, it is the clear choice, and where they are not, decide on whether your design is governed by capacity or by tonnage.

Common questions

W 12X87 is the stronger of the two in bending, with a plastic modulus of 2163.1 cm³ against 2081.2 cm³ - 3.9% more. At the same steel grade that translates directly into moment capacity, since M_pl,Rd = W_pl x f_y / gamma_M0.

W 12X87 at 129.5 kg/m, against 132.4 kg/m for the other - a saving of 2.2%. Over a repeated floor beam that is a real cost difference, but check it against the deflection case before taking it.

Structurally it is the closest equivalent we hold: HP 12X89 gives 2081.2 cm³ of plastic modulus and 28,845 cm⁴ of inertia against 2163.1 cm³ and 30,801 cm⁴. Re-check deflection and the connection details before swapping, since the flange and web thicknesses differ.

W 12X87, with a second moment of area of 30,801 cm⁴ against 28,845 cm⁴ (6.8% more). Deflection under a uniform load goes as 5wL⁴/384EI, so it is inversely proportional to I - on a span where the deflection limit governs rather than strength, this is the number that decides the section.

Related comparisons

W 12X87 vs HE 320 BW 12X87 vs H-350x350x10x16-115HE 320 B vs HP 12X89
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