Sheet Steel: Gauge, Thickness, and Weight Chart

By Jack Gray, Roof Online Editor • Last updated August 6, 2024

Table of Contents

A sheet steel patch on an old steel roof deck.
A piece of 24-gauge galvanized steel used to patch a rusted area of steel roof deck

About These Sheet Steel Weights

The values provided in the table are standards; real-life products will vary.

These values should not be used if extreme precision is needed for critical engineering calculations. When such precision is required, always refer to the data sheets of the actual, specific product you intend to use, or better yet, contact the technical department of the product manufacturer.

Manufacturer technical data sheets (with the sheet steel weights and thicknesses) are almost always made available on the websites of reputable manufacturers.

Table: Sheet Steel Weights and Thicknesses

Thickness and Weight of Sheet Steel by Gauge
GaugeThickness:
Manufacturers’ Standard Gauge
(Decimal Inches)
Weight:
Pounds per Square Foot (lb/ft2)
Thickness:
Manufacturer’s Standard Gauge
(Millimeters)
Weight:
Kilograms per Square Meter
(kg/m2)
Examples of Use
Add 0.00375 for
Galvanized Steel
Add 0.156 for Galvanized SteelAdd 0.095 for Galvanized SteelAdd 0.762 for Galvanized Steel
30.2391
inch
10
lb/ft2
6.07
mm
48.824
kg/m2
house foundation bearing plate
40.2242
inch
9.375
lb/ft2
5.69
mm
45.773
kg/m2
automotive leaf spring
50.2092
inch
8.750
lb/ft2
5.31
mm
42.721
kg/m2
seawall panels, heavy retaining wall panels
60.1943
inch
8.125
lb/ft2
4.94
mm
39.670
kg/m2
machine tool housing/cabinet
70.1793
inch
7.500
lb/ft2
4.55
mm
36.618
kg/m2
saw mill blades
80.1644
inch
6.875
lb/ft2
4.18
mm
33.567
kg/m2
walls of large commercial grain bins
90.1495
inch
6.250
lb/ft2
3.80
mm
30.515
kg/m2
home safe, gun safe wall construction
100.1345
inch
5.625
lb/ft2
3.42
mm
27.464
kg/m2
residential storm shelter wall construction
110.1196
inch
5.000
lb/ft2
3.04
mm
24.412
kg/m2
weldable automobile frame patches
120.1046
inch
4.375
lb/ft2
2.66
mm
21.361
kg/m2
heavy duty eave struts in steel buildings
130.0897
inch
3.750
lb/ft2
2.28
mm
18.309
kg/m2
metal flooring plates
140.0747
inch
3.125
lb/ft2
1.90
mm
15.258
kg/m2
heavy duty corner angle/corner braces
150.0673
inch
2.813
lb/ft2
1.71
mm
13.734
kg/m2
tractor fenders
160.0598
inch
2.500
lb/ft2
1.52
mm
12.206
kg/m2
roof truss gusset plates, heavy gauge roof deck
170.0538
inch
2.250
lb/ft2
1.37
mm
10.985
kg/m2
steel wheelbarrow tub
180.0478
inch
2.000
lb/ft2
1.21
mm
9.765
kg/m2
medium gauge roof deck, traffic signs
190.0418
inch
1.750
lb/ft2
1.06
mm
8.544
kg/m2
auto body panels
200.0359
inch
1.500
lb/ft2
0.91
mm
7.324
kg/m2
medium gauge roof deck
210.0329
inch
1.375
lb/ft2
0.84
mm
6.713
kg/m2
workshop tool chest cabinet
220.0299
inch
1.250
lb/ft2
0.76
mm
6.103
kg/m2
light gauge roof deck
230.0269
inch
1.125
lb/ft2
0.68
mm
5.493
kg/m2
overhead/rolling door section panels
240.0239
inch
1.000
lb/ft2
0.61mm4.882
kg/m2
metal parapet wall coping
250.0209
inch
0.875
lb/ft2
0.53
mm
4.272
kg/m2
corrugated metal roof panels
260.0179
inch
0.750
lb/ft2
0.45
mm
3.662
kg/m2
typical standing seam metal roof panels
270.0164
inch
0.688
lb/ft2
0.42
mm
3.359
kg/m2
foam composite garage door panel exterior skin
280.0149
inch
0.625
lb/ft2
0.38
mm
3.052
kg/m2
substrate for lightweight insulating concrete
290.0135
inch
0.563
lb/ft2
0.34
mm
2.749
kg/m2
lightest gauge standing seam metal roof panels
300.0120
inch
0.500
lb/ft2
0.30
mm
2.441
kg/m2
round sheet metal pipe for HVAC ducts
310.0105
inch
0.438
lb/ft2
0.27
mm
2.139
kg/m2
lightweight corrugated roof and wall panels
320.0097
inch
0.406
lb/ft2
0.25
mm
1.982
kg/m2
galvanized steel step flashings
330.0090
inch
0.375
lb/ft2
0.23
mm
1.831
kg/m2
residential plumbing vent roof jack
340.0082
inch
0.344
lb/ft2
0.21
mm
1.680
kg/m2
toy-making, model-building
350.0075
inch
0.313
lb/ft2
0.19
mm
1.528
kg/m2
shim stock for leveling machine parts
360.0067
inch
0.281
lb/ft2
0.17
mm
1.372
kg/m2
370.0064
inch
0.266
lb/ft2
0.16
mm
1.299
kg/m2
380.0060
inch
0.250
lb/ft2
0.15
mm
1.221
kg/m2

Manufacturers’ Standard Gauge for Sheet Steel

The table below provides sheet steel weights and thicknesses in both US and metric according to the Manufacturers’ Standard Gauge for Sheet Steel (MSG), which is the primary commercial gauge system used by sheet steel manufacturers in the United States today.

The Manufacturers’ Standard Gauge for Sheet Steel assumes an average density for carbon steel of 41.82 lbs. per square foot per inch thick. The precise thickness for each gauge is established by the standard. The standard sheet steel weight for each gauge number is derived from these standards.

When you buy sheet steel, these are typically the weights and thicknesses you’ll be getting, although actual finished products may vary slightly according to industry-accepted manufacturing tolerances (small variations from the standard due to the practicalities of the manufacturing process).

These tolerances go from around (+ -) 4.5% for 10 gauge steel to around 8.5% for 15 gauge steel and higher. (If these were rocket ship parts, the tolerances would be much, much smaller.) A full table of ASTM-AISI standard sheet steel tolerances by gauge number can be seen here.

The Old Standard Sheet Steel Gauge

The U.S. Standard Gauge for Sheet and Plate Iron and Steel is not the same as the Manufacturers’ Standard Gauge and should not normally be referred to when calculating sheet steel weight. It is not generally used for commercial purposes any more.

If you’d like to take a look at the U.S. Standard Gauge (which is, in fact, a part of the U.S. legal code) see this page at the Cornell Law School website.

Galvanized Sheet Steel Weight and Thickness

Galvanized steel is formed by applying a very thin coating of zinc to a steel sheet.

Approximately the same amount of zinc is applied regardless of the gauge of the steel, so the thickness and weight of galvanized steel by gauge can be determined by adding a constant to the values for the plain steel gauges (see the table below).

Corrugated Sheet Steel Weight

Corrugated steel, which is used for roof decks and some roof and wall panels, will weigh from 30% to 70% more per square foot as a finished product than flat sheet steel of the same gauge due to the corrugation.

The exact increase in weight depends on the depth and spacing of the ribs, which varies from product to product. The weight per square foot should be available on the website of the manufacturer.

Sheet Steel Gauge Measuring Tool

If you need to identify or verify the gauge of a piece of sheet steel (if you need to know the gauge of an existing steel roof deck, for example), see this useful and inexpensive tool on Amazon.

You can also see product information for sheet steel at the Home Depot.

What is Gauge when Talking about Sheet Steel?

When referring to metal, “gauge” is a standardized measurement of the thickness of the product in question, generally sheet steel, steel plate, or wire. Sheet steel thickness decreases as the gauge number increases.

There are a couple of explanations for the origin of gauge as a measure of sheet steel thickness, and why sheet steel thickness goes down while the gauge number goes up.

Both explanations start back in the early days of the Industrial Revolution in England, when new industrial standards were being created left and right.

New standards were needed to ensure that all of the new manufacturers of new industrial materials would be producing interchangeable products that their customers could rely on to be practically identical regardless of the producer.

These industry-wide standards gave a massive boost to efficiency. Standardization was one of the prime drivers of the Industrial Revolution.

One explanation of the origins of gauge as a measure of sheet steel weight and thickness says that the concept of gauge was borrowed from the wire industry.

Wire is produced by being drawn (essentially using machine tools to pull it through a hole to make it thinner). Wire gauge was determined by how many times a piece of wire was drawn through smaller and smaller holes. And the more times it was drawn, the thinner and lighter it was.

The wire industry standardized wire measurement by using the gauge system to specify the diameter of wire. So this explanation of sheet steel gauge says the sheet steel producers simply adopted the gauge system of weight and thickness from the wire industry.

The other explanation is that sheet steel manufacturers established a standard weight per square foot for a one-inch-thick steel plate, and then took this standard as a starting point. The sheet steel gauge number referred to how many sheets of a particular thickness would fit into an inch.

That is, sheet steel gauge referred to the fraction of an inch that the thickness of the sheet was. A 20-gauge sheet of steel would be 1/20 of an inch thick, and so on.

Sheet steel weight for a particular gauge number would simply reflect the standardized density of steel and the standardized thickness of that gauge number.

Over time, for one reason or another, so many sheet steel manufacturers began deviating from the standard that new standards had to be established to reflect reality.

That’s why current gauges aren’t precise fractions of an inch, and that’s how we got to where we are today. At least that’s the story.


About the Author

Jack Gray is a principal roof consultant and vice president at the Moriarty Corporation, an award-winning building enclosure consultant firm founded in 1967. He is also the editor of the Roof Online website.

Mr. Gray has worked in the roofing industry for over 25 years, with training and practical experience in roof installation, roof inspection, roof safety, roof condition assessment, construction estimating, roof design & specification, quality assurance, roof maintenance & repair, and roof asset management.

He was awarded the Registered Roof Observer (RRO) professional credential in 2009.

He also served as an infantry paratrooper in the 82nd Airborne Division and has a B.A. from Cornell University. Read full bio.


  1. Metal Roof and Wall Panels
  2. Metal Roofing Product Manufacturers
  3. Oil Canning in Metal Roof Panels
  4. Weight of Plywood and OSB
  5. Weight of Roofing Materials
  6. Weights of Metals