A sheet metal gauge (sometimes spelled "gage") indicates the standard thickness of sheet metal for a specific material. As the gauge number increases, the material thickness decreases.
Sheet metal thickness gauges for steel are based on a weight of 41.82 pounds per square foot per inch of thickness. This is known as the Manufacturers' Standard Gage for Sheet Steel. Gauges for sheet metals typically range from 07 to 30, with numbers after 31 uncommon and without standard thickness values.
For other materials, such as aluminum and brass, the thicknesses will be different. Thus, a 10-gauge steel sheet which has a thickness of 0.1345 inches will weigh 41.82*0.1345 = 5.625 pounds per square foot.
Examples: 16 ga CRS is 2.5 pounds per square foot. For 18 ga CRS the weight is 2.0 pounds per square foot and for 20 ga CRS the weight is 1.5 pounds per square foot.
STANDARD SHEET METAL GAUGES
| Gauge | Steel | Carbon Steel eh | Galvanized Steel | Stainless Steel | Aluminum | Steel (mm) |
|---|---|---|---|---|---|---|
| 07 | 0.179 | - | - | - | - | 4.547 |
| 08 | 0.165 | 0.1644 | 0.1681 | 0.1719 | 0.1285 | 4.191 |
| 09 | 0.150 | 0.1495 | 0.1532 | 0.1563 | 0.1144 | 3.810 |
| 10 | 0.135 | 0.1345 | 0.1382 | 0.1406 | 0.1019 | 3.429 |
| 11 | 0.120 | 0.1196 | 0.1233 | 0.1250 | 0.0907 | 3.048 |
| 12 | 0.105 | 0.1046 | 0.1084 | 0.1094 | 0.0808 | 2.677 |
| 13 | 0.090 | - | - | 0.094 | 0.072 | 2.286 |
| 14 | 0.075 | 0.0747 | 0.0785 | 0.0781 | 0.0641 | 1.905 |
| 15 | 0.067 | - | - | 0.070 | 0.057 | 1.702 |
| 16 | 0.060 | 0.0598 | 0.0635 | 0.0625 | 0.0508 | 1.524 |
| 17 | 0.054 | - | - | 0.056 | 0.045 | 1.372 |
| 18 | 0.048 | 0.0478 | 0.0516 | 0.0500 | 0.0403 | 1.219 |
| 19 | 0.042 | - | - | 0.044 | 0.036 | 1.067 |
| 20 | 0.036 | 0.0359 | 0.0396 | 0.0375 | 0.0320 | 0.9144 |
| 21 | 0.033 | - | - | 0.034 | 0.028 | 0.838 |
| 22 | 0.030 | - | - | 0.031 | 0.025 | 0.762 |
| 23 | 0.027 | - | - | 0.028 | 0.023 | 0.686 |
| 24 | 0.024 | - | - | 0.025 | 0.020 | 0.610 |
| 25 | 0.021 | - | - | 0.022 | 0.018 | 0.533 |
| 26 | 0.018 | - | - | 0.019 | 0.017 | 0.457 |
| 27 | 0.016 | - | - | 0.017 | 0.014 | 0.406 |
| 28 | 0.015 | - | - | 0.016 | - | 0.381 |
| 29 | 0.014 | - | - | 0.014 | - | 0.356 |
| 30 | 0.012 | - | - | 0.013 | - | 0.305 |
| 31 | - | - | 0.011 | - |
• Thickness is expressed in inches except for the mm column (1in = 25.4mm).
• This table is for reference only and it is highly recommended that you check with a local supplier to establish what actual thickness values are used in your geographic area.
