Common Thicknesses of Sheet Metals

  • Traditional unit of measurement listed first.
  • Preferred units are marked *, are usually actual rather than nominal; mm equivalents are calculated, rounded to 2 decimal places.
  • Verify appropriate level of precision for application.
  • Heavy line indicates structurally equivalent flashing thicknesses (approximate).
  • Shaded boxes indicate thicknesses readily available.
  • Costs are given to suggest relative cost differences only.

Sources:               

  • SMACNA Architectural Metal Manual, 4th Edition.
  • AISC Manual of Steel Construction, 6th edition (old gage equivalents)
  • Cost/sf from 2007 Means BCCD; for flashing material except for steel, which is an extrapolation of roof panel costs.
                               

Steel

gage

12

14

16

18

19

20

21

22

23

24

25

26

28

 
 

inches*

0.105

0.075

0.06

0.048

0.042

0.0359

0.033

0.0299

0.0269

0.0239

0.0209

0.0179

0.0149

 
 

mm

2.67

1.91

1.52

1.22

1.09

0.91

0.84

0.76

0.68

0.61

0.53

0.45

0.38

 
 

lb/sf (no coat)

4.375

3.125

2.5

2.0

1.750

1.5

1.375

1.25

1.125

1.0

0.875

0.75

0.625

 
 

Cost/sf

             

2.27

 

1.99

 

0.86

1.22

 

Stainless

ga

     

18

19

20

21

22

23

24

25

26

28

32

 

inches*

     

0.050

0.044

0.0375

0.0344

0.0313

0.028

0.025

0.022

0.019

0.015

0.010

 

mm

     

1.27

1.12

0.95

0.87

0.79

0.71

0.64

0.56

0.48

0.38

0.25

 

lb/sf

     

2.1

1.84

1.575

1.444

1.313

1.181

1.050

0.92

0.788

   
 

Cost/sf

                 

6.10

 

4.71

3.89

3.13

Aluminum

inches*

0.081

0.064

0.051

0.040

 

0.032

 

0.025

 

0.020

 

0.016

0.012

 
 

mm

2.06

1.63

1.29

1.0

 

0.81

 

0.64

 

0.51

 

0.41

0.33

 
 

B&S gage

12

14

16

18

 

20

 

22

 

24

 

26

28

 
 

lb/sf

 

0.901

0.72

0.563

 

0.541

 

0.352

 

0.282

 

0.224

0.177

 
 

Cost/sf

   

2.01

1.77

 

1.18

     

0.82

 

0.63

0.43

 

Copper

oz/sf

   

36

32

28

24

20

18

16

15

14

13

   
 

inches*

   

0.048

0.043

0.038

0.032

0.027

0.024

0.022

0.0202

0.0189

0.0175

   
 

mm

   

1.22

1.09

0.97

0.81

0.69

0.61

0.56

0.51

0.48

0.44

   
 

ga

   

16

17

19

20

21

22

23

24

25

26

   
 

lb/sf

   

2.25

2.0

1.75

1.5

1.25

1.125

1.0

0.938

0.875

0.813

   
 

Cost/sf

     

10.60

 

7.95

6.50

 

5.05

         

Terne-

inches*

                     

0.018

0.015

0.012

coated

mm

                     

0.48

0.38

0.31

stainless

ga

                     

26

28

30

 

lb/sf   (coat.)

                           
 

Cost/sf

                     

6.85

6.05

 

Zinc-

inches*

     

0.040

   

0.032

 

0.027

 

0.020

     

Copper

mm

     

1.0

   

0.81

 

0.69

 

0.51

     

alloy

lb/sf

               

1.0

 

0.75

     
 

Cost/sf

     

8.15

   

6.65

 

5.70

 

4.26

     

Lead

lb/sf

6

4

 

3.0

2.5

2.0

               
 

inches*

0.0937

0.0625

 

0.0468

0.039

0.0312

               
 

mm

2.35

1.55

 

1.19

0.99

0.79

               
 

Cost/sf

       

3.03