Joists - 127x76x16

A structural steel joist, also known as a Rolled Steel Joist (RSJ) is a solid, single piece of structural steel hot-rolled into an "I" or "H" shaped profile. It features a vertical central section (the web) that resists shearing forces, and horizontal top and bottom plates (the flanges) that prevent bending. Unlike modern Universal Beams (UBs) which have perfectly parallel flanges, classic RSJs feature slightly tapered, sloping inner flanges. They are incredibly strong, compact, and are the everyday "default" choice in UK residential construction for spanning wide openings, building extensions, and supporting load-bearing walls.

Dimensions

PropertyValue
kg/m16.5
D mm127
B mm76.2
t mm5.6
T mm9.6
r1 mm9.4
r2 mm4.6
d mm86.5
b/T3.97
d/t15.4
C mm5
N mm42
n mm22
m20.512
m231

Full sortable table: Dimensions table for this category

Section Properties

PropertyValue
Second Moment of Area (x-x) - cm4571
Second Moment of Area (y-y) - cm460.8
Radius of Gyration (x-x) - cm5.21
Radius of Gyration (y-y) - cm1.7
Elastic Modulus (x-x) - cm390
Elastic Modulus (y-y) - cm316
Plastic Modulus (x-x) - cm3104
Plastic Modulus (y-y) - cm326.4
Buckling Parameter - u0.891
Torsional Index - x11.8
Warping Constant - H dm60.0021
Torsional Constant - J cm46.72
Area of Section - A cm221.1

Full sortable table: Properties table for this category