Thermal conductivity of building materials

Abstracted from ASHRAE (1989), with permission

Building Board

Description

Density
kg/m3

Conductivity
W/(m·K)

Gypsum or plasterboard, 0.5 in

800

0.160

Plywood (Douglas fir)

545

0.115

Hardboard, Medium-density

800

0.105

Hardboard, High-density, service temp. service underlay

880

0.118

Hardboard, High-density. standard tempered

1010

0.144

Particleboard, Low-density

593

0.078

Particleboard, Medium-density

800

0.135

Particleboard, High-density

1000

0.170

Insulation

Description

Density
kg/m3

Conductivity
W/(m·K)

Cellular glass

136

0.050

Glass fiber, organic bonded

64 to 144

0.036

Expanded perlite, organic bonded

16

0.052

Expanded rubber (rigid)

72

0.032

Expanded polystyrene extruded, Cut cell surface

29

0.036

Expanded polystyrene extruded, Smooth skin surface

29 to 56

0.029

Expanded polystyrene, molded beads

16

0.029

20

0.036

24

0.035

28

0.035

32

0.033

Cellular polyurethane (R11 exp.)(unfaced)

24

0.023

Polyisocynaurate (R11 exp.)

32

0.020

Mineral fiber with resin binder

240

0.042

Mineral fiberboard, wet-felted, Core or roof insulation

256 to 272

0.049

Mineral fiberboard, wet-felted, Acoustical tile

288

0.050

Loose Fill

Description

Density
kg/m3

Conductivity
W/(m·K)

Cellulosic insulation (milled paper or wood pulp)

37 to 51

0.039 to 0.046

Sawdust or shavings

128 to 240

0.065

Wood fiber, softwoods

32 to 56

0.043

Perlite, expanded

80 to 128

0.053

Vermiculite, exfoliated

112 to 131

0.068

Masonry materials / Concrete

Description

Density
kg/m3

Conductivity
W/(m·K)

Cement motor

1860

0.72

Lightweight aggregates including expanded shale, clay or slate; expanded slags; cinders; pumice; vermiculite; also cellular concretes

1920

0.75

1600

0.52

1280

0.36

960

0.24

640

0.17

Perlite, expanded

640

0.13

Sand and gravel or stone aggregate (oven-dried)

2240

1.30

Sand and gravel or stone aggregate (not dried)

2240

1.73

Stucco

1860

0.72

Masonry units

Description

Density
kg/m3

Conductivity
W/(m·K)

Brick, common

1920

0.72

Brick, face

2080

1.30

Siding material (on flat surface)

Description

Density
kg/m3

Conductivity
W/(m·K)

Hardboard siding, 7/16 in

640

0.094

Woods

Description

Density
kg/m3

Conductivity
W/(m·K)

Maple, oak, and similar hardwoods

720

0.16

Fir, pine, etc.

510

0.12