Product Comparison

R-VALUES FOR FOAMULAR
®
XPS PRODUCTS
FOAMULAR
®
Extruded Polystyrene (XPS) Insulation
Thickness
Thermal Resistance,
R-Value (180 day) minimum
hr•ft
2
•°F/Btu
Long Term Thermal Resistance,
LTTR-Value, minimum
hr•ft
2
•°F/Btu
@ 75º F @ 40º F @ 75º F
FOAMULAR
®
XPS Products
½ "* 3.0 3.2 N/A
¾ "* 4.0 4.3 N/A
1" 5.0 5.4 5.0
1½ " 7.5 8.1 7.8
2" 10.0 10.8 10.6
2½ " 12.5 13.5 13.4
3" 15.0 16.2 16.2
4" 20.0 21.6 22.0
High R CW Plus
1¾ " 10.0 10.8 10.3
2
1
⁄
8
" 12.0 13.0 12.5
3" 17.0 18.4 14.7
*R-value for FOAMULAR
®
IS and PROPINK
®
sheathing.
Note: R means the resistance to heat  ow; the higher the
value, the greater the insulation power. The insulation must
be installed properly to get the marked R-value. Follow the
manufacturer’s instructions carefully. If a manufacturer’s fact
sheet is not provided with the material shipment, request
this and review it carefully. R-values vary depending on
many factors including the mean temperature at which the
test is conducted, and the age of the sample at the time
of testing. Because rigid foam plastic insulation products
are not all aged in accordance with the same standards, it
is useful to publish comparison R-value data. The R-values
for FOAMULAR
®
XPS insulation are provided from testing
at two mean temperatures, 40ºF and 75ºF, and from two
aging (conditioning) techniques, 180 day real time aged (as
mandated by ASTM C578) and a method of accelerated aging
sometimes called “Long Term Thermal Resistance” (LTTR)
per CAN/ULC S770. The R-value at 180 day real-time age
and 75ºF mean temperature is commonly used to compare
products and is the value printed on the product.