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### About the Thermal Expansion Chart

The following table provides the coefficients of linear thermal expansion and representative thermal expansion values for various building materials.

Where possible, the values were taken directly from manufacturer technical data sheets and reflect the coefficients of linear thermal expansion for specific, representative products.

In a few cases, the values we give were calculated by averaging manufacturer or producer data from more than one source, or were taken from a non-commercial source that we consider authoritative.

We discuss thermal expansion here, but everything applies in reverse as the temperature decreases and the material contracts.

### What is the Coefficient of Linear Thermal Expansion?

The coefficient of linear thermal expansion (CLTE) is the change in the length of a quantity of material as a fraction of the original length of the material per degree of temperature change.

So when you see a manufacturer’s technical data sheet express the CLTE as “in/in•°F” (or very often as “in/in/°F”), you can read that as “change in length (measured in inches) per inch per degree.

### Coefficient of Linear Thermal Expansion Explained

If the CLTE of a material is one millionth of an inch, that means that for every degree of temperature increase, one inch of the material will expand to be 1.000001 inches long.

For a ten foot long (120 inches) piece of material (a sheet of metal, for example), that translates into an increase of 120 millionths of an inch for the whole piece of material for a one degree change.

For a 100 degree increase, that means the original ten foot section will add 12,000 millionths of an inch to its length. The original ten foot section will now be 10 feet and 0.012 inches long.

(One millionth of an inch is not a typical CLTE, all of the materials listed below have much larger CLTE’s.)

### Variations in Thermal Expansion Values

Please note that variations in product material formulations, differences in manufacturing processes, and the temperature range during the expansion or contraction (e.g., the temperature rises from 0°F to 50°F vs. rising from 70°F to 120°F) can all affect actual thermal expansion values.

Built-up roof membranes, for instance, have much larger CLTE’s from -20°F to +30°F than they do from +80°F to +130°F. The CLTE of concrete varies according to the type of aggregate material used in the mix.

The roofing membrane materials listed below will typically develop smaller CLTE’s as they age.

### Check with the Manufacturer!

These thermal expansion values are meant to provide a general idea of how much various materials expand and contract due to temperature change, and should not be used if precise values are needed for critical engineering calculations.

When precision is necessary, always refer to the data sheets of the actual, specific product you intend to use. If the data sheets do not provide a coefficient of linear thermal expansion, contact the technical department of the product manufacturer or material provider.

See our Manufacturer Directory for a huge list of building product manufacturers’ websites.

### Table of Coefficients of Linear Thermal Expansion for Building Materials

To convert inch decimals to fractions, see our Inch Fractions to Decimals to Millimeters Table.

Linear Thermal Expansion of Building Materials

Material Coefficient of Linear Thermal Expansion
(in/in•°F)
Change in Length for a 10 Foot Section per 100°F Temperature Change Coefficient of Linear Thermal Expansion
(m/m•°C)
Change in Length for a 1 Meter Section per 50°C Temperature Change
Aluminum 0.0000130
(13 x 10^-6)
0.156 inch 0.0000234
(23.4 x 10^-6)
1.17 mm
Brass 0.0000104
(10.4 x 10^-6)
0.1248 inch 0.0000187
(18.7 x 10^-6)
0.935 mm
Brick Masonry 0.0000031
(3.1 x 10^-6)
0.0372 inch 0.0000056
(5.6 x 10^-6)
0.28 mm
Built-up Roof Membrane, Asphalt 0.0001200
(120 x 10^-6)
1.44 inch 0.0002160
(216 x 10^-6)
10.8 mm
Built-up Roof Membrane, Coal Tar Pitch 0.0001550
(155 x 10^-6)
1.86 inch 0.0002790
(279 x 10^-6)
13.95 mm
Cement 0.0000060
(6 x 10^-6)
0.072 inch 0.0000108
(10.8 x 10^-6)
0.54 mm
Clay Tile 0.0000033
(3.3 x 10^-6)
0.0396 inch 0.0000059
(5.9 x 10^-6)
0.295 mm
Concrete, Lightweight Insulating 0.0000060
(6 x 10^-6)
0.072 inch 0.0000108
(10.8 x 10^-6)
0.54 mm
Concrete, Structural 0.0000057
(5.7 x 10^-6)
0.0684 inch 0.0000103
(10.3 x 10^-6)
0.515 mm
Copper 0.0000098
(9.8 x 10^-6)
0.1176 inch 0.0000176
(17.6 x 10^-6)
0.88 mm
EPDM Roof Membrane 0.0000570
(57 x 10^-6)
0.684 inch 0.0001026
(102.6 x 10^-6)
5.13 mm
Fiber Cement 0.0000067
(6.7 x 10^-6)
0.0804 inch 0.0000121
(12.1 x 10^-6)
0.605 mm
Glass 0.0000047
(4.7 x 10^-6)
0.0564 inch 0.0000085
(8.5 x 10^-6)
0.425 mm
Gypsum Board 0.0000080
(8 x 10^-6)
0.096 inch 0.0000144
(14.4 x 10^-6)
0.72 mm
Iron 0.0000067
(6.7 x 10^-6)
0.0804 inch 0.0000121
(12.1 x 10^-6)
0.605 mm
(16.4 x 10^-6)
0.1968 inch 0.0000295
(29.5 x 10^-6)
1.475 mm
Modified Bitumen Roof Membrane, APP 0.0001850
(185 x 10^-6)
2.22 inch 0.0003330
(333 x 10^-6)
16.65 mm
Modified Bitumen Roof Membrane, SBS 0.0001650
(165 x 10^-6)
1.98 inch 0.0002970
(297 x 10^-6)
14.85 mm
Monel 0.0000078
(7.8 x 10^-6)
0.0936 inch 0.0000140
(14 x 10^-6)
0.7 mm
Neoprene 0.0000760
(76 x 10^-6)
0.912 inch 0.0001368
(136.8 x 10^-6)
6.84 mm
Perlite Board Insulation 0.0000120
(12 x 10^-6)
0.144 inch 0.0000216
(21.6 x 10^-6)
1.08 mm
Plaster 0.0000092
(9.2 x 10^-6)
0.1104 inch 0.0000166
(16.6 x 10^-6)
0.83 mm
Polycarbonate 0.0000388
(38.8 x 10^-6)
0.4656 inch 0.0000698
(69.8 x 10^-6)
3.49 mm
Polyethylene 0.0001110
(111 x 10^-6)
1.332 inch 0.0001998
(199.8 x 10^-6)
9.99 mm
Polyisocyanurate 0.0000350
(35 x 10^-6)
0.42 inch 0.0000630
(63 x 10^-6)
3.15 mm
Polystyrene, Expanded 0.0000350
(35 x 10^-6)
0.42 inch 0.0000630
(63 x 10^-6)
3.15 mm
Polystyrene, Extruded 0.0000350
(35 x 10^-6)
0.42 inch 0.0000630
(63 x 10^-6)
3.15 mm
Polyurethane Foam, Spray, Closed Cell 0.0000180
(18 x 10^-6)
0.216 inch 0.0000324
(32.4 x 10^-6)
1.62 mm
Polyurethane Foam, Spray, Open Cell 0.0001800
(180 x 10^-6)
2.16 inch 0.0003240
(324 x 10^-6)
16.2 mm
PVC Roof Membrane 0.0000580
(58 x 10^-6)
0.696 inch 0.0001044
(104.4 x 10^-6)
5.22 mm
PVC, Rigid 0.0000300
(30 x 10^-6)
0.36 inch 0.0000540
(54 x 10^-6)
2.7 mm
Steel 0.0000067
(6.7 x 10^-6)
0.0804 inch 0.0000121
(12.1 x 10^-6)
0.605 mm
Steel, Galvanized 0.0000067
(6.7 x 10^-6)
0.0804 inch 0.0000121
(12.1 x 10^-6)
0.605 mm
Steel, Stainless 0.0000098
(9.8 x 10^-6)
0.1176 inch 0.0000176
(17.6 x 10^-6)
0.88 mm
Stone, Granite 0.0000044
(4.4 x 10^-6)
0.0528 inch 0.0000079
(7.9 x 10^-6)
0.395 mm
Stone, Limestone 0.0000033
(3.3 x 10^-6)
0.0396 inch 0.0000059
(5.9 x 10^-6)
0.295 mm
Stone, Marble 0.0000056
(5.6 x 10^-6)
0.0672 inch 0.0000101
(10.1 x 10^-6)
0.505 mm
Stone, Sandstone 0.0000065
(6.5 x 10^-6)
0.078 inch 0.0000117
(11.7 x 10^-6)
0.585 mm
Stone, Slate 0.0000058
(5.8 x 10^-6)
0.0696 inch 0.0000104
(10.4 x 10^-6)
0.52 mm
Stucco 0.0000070
(7 x 10^-6)
0.084 inch 0.0000126
(12.6 x 10^-6)
0.63 mm
Terracotta 0.0000029
(2.9 x 10^-6)
0.0348 inch 0.0000052
(5.2 x 10^-6)
0.26 mm
Terne 0.0000067
(6.7 x 10^-6)
0.0804 inch 0.0000121
(12.1 x 10^-6)
0.605 mm
Tin 0.0000117
(11.7 x 10^-6)
0.1404 inch 0.0000211
(21.1 x 10^-6)
1.055 mm
TPO Roof Membrane 0.0000440
(44 x 10^-6)
0.528 inch 0.0000792
(79.2 x 10^-6)
3.96 mm
Vinyl Siding 0.0000330
(33 x 10^-6)
0.396 inch 0.0000594
(59.4 x 10^-6)
2.97 mm
Wood, Average
(across the grain)
0.0000250
(25 x 10^-6)
0.3 inch 0.0000450
(45 x 10^-6)
2.25 mm
Wood, Average
(with the grain)
0.0000025
(2.5 x 10^-6)
0.03 inch 0.0000045
(4.5 x 10^-6)
0.225 mm
Wood, Cedar
(with the grain)
0.0000025
(2.5 x 10^-6)
0.03 inch 0.0000045
(4.5 x 10^-6)
0.225 mm
Wood Fiberboard Insulation 0.0000090
(9 x 10^-6)
0.108 inch 0.0000162
(16.2 x 10^-6)
0.81 mm
Wood, Fir
(with the grain)
0.0000021
(2.1 x 10^-6)
0.0252 inch 0.0000038
(3.8 x 10^-6)
0.19 mm
Wood, Fir
(across the grain)
0.0000320
(32 x 10^-6)
0.384 inch 0.0000576
(57.6 x 10^-6)
2.88 mm
Wood, Oak
(with the grain)
0.0000027
(2.7 x 10^-6)
0.0324 inch 0.0000049
(4.9 x 10^-6)
0.245 mm
Wood, OSB 0.0000031
(3.1 x 10^-6)
0.0372 inch 0.0000056
(5.6 x 10^-6)
0.28 mm
Wood, Pine
(with the grain)
0.0000031
(3.1 x 10^-6)
0.0372 inch 0.0000056
(5.6 x 10^-6)
0.28 mm
Wood, Plywood 0.0000034
(3.4 x 10^-6)
0.0408 inch 0.0000061
(6.1 x 10^-6)
0.305 mm
Wood, Spruce
(with the grain)
0.0000025
(2.5 x 10^-6)
0.03 inch 0.0000045
(4.5 x 10^-6)
0.225 mm
Zinc 0.0000174
(17.4 x 10^-6)
0.2088 inch 0.0000313
(31.3 x 10^-6)
1.565 mm