Property*

Units

Requirements

Test Method

Type 1

Type 2

Type 3

Thermal Resistance

 (R-value)

Minimum @ at 24C (75°F)

m²•°C/ (W•25 mm)

0.65

0.70

0.74

ASTM C518

ft²•hr•°F/(BTU•in)

3.75

4.04

4.27

Water Vapour Permeance**

Maximum

ng/(Pa•s•m² )

300

200

130

ASTM E96

perms

5.2

3.2

2.3

Dimensional Stability

Maximum

% linear change

1.5

1.5

1.5

ASTM D2126

7 days @ 70± 2°C

Flexural Strength

Minimum

kPa

170

240

300

ASTM C203

Procedure B

psi

25

35

44

Water Absorption

Maximum

% by volume

6.0

4.0

2.0

ASTM D2842

Compressive Strength

Minimum @ 10% Deformation

kPa

70

110

140

ASTM D1621

Procedure A

psi

10

16

20

Limiting Oxygen Index

Minimum

%

24

24

24

ASTM D2863

**The test methods used to determine the above material properties provide a means of comparing different cellular plastic thermal insulations.  They are intended for use in specifications, product evaluations and quality control.  They are not intended to predict end-use product performance.

*Values quoted are maximum values for 25 mm (1 inch) thick samples with natural skins intact.  Lower values will result for thicker materials.