PLUS+ Compared to XPS

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PLUS+ Compared to XPS


There are market place misconceptions on the performance of PLUS+ compared to XPS insulation. Consider these facts and make an educated decision.

Foam-Control PLUS+   XPS
ASTM C578 Standard Compliance.
Foam-Control PLUS+ is manufactured in compliance with ASTM C578, “Standard Specification for Rigid, Cellular Polystyrene Thermal Insulation”.
ASTM C578 Standard Compliance.
XPS is manufactured in compliance with ASTM C578, “Standard Specification for Rigid, Cellular Polystyrene Thermal Insulation”.
UL and ICC-ES Recognition.
Foam-Control PLUS+ is recognized in UL ER11812-01 and ICC-ES ESR-1006 evaluation reports.
Limited Recognition.
Code reports for XPS are not available from UL. Some, but not all manufacturers have ICC-ES reports.
Closed Cell Polystyrene Foam Filled with Air.
Foam-Control PLUS+ is a closed cell foam. It is manufactured from expanded polystyrene resin which is molded into blocks. Foam-Control PLUS+ contains air within the closed cells.
Closed Cell Polystyrene Foam Filled with an Unknown Gas.
XPS is a closed cell foam. It is manufactured from polystyrene, blowing agents, and dyes which are extruded into boards. XPS generally contains HFC’s such as HFC 134a within the closed cells. HFC’s are harmful to the environment.
R-value: Stable Long-Term.
Foam-Control PLUS+ is stable and the R-value will not change with time.
R-value: Loses R-value over Time.
XPS is not stable and the R-value will drop over time as the cell gases escape.
Excellent Water Resistance.
Foam-Control PLUS+ is a closed cell polystyrene foam which is naturally water resistant. Foam-Control PLUS+ has demonstrated lower water absorption than XPS in several long-term exterior exposure studies. Don’t be fooled by comparisons using short term laboratory tests which are conducted for only 24 hours.
Excellent Water Resistance.
XPS is a closed cell polystyrene foam which is naturally water resistant. The water resistance of XPS is published for exposure to water in a laboratory after only 24 hours. Short term laboratory results do not correlate to long-term performance of XPS in exterior exposure conditions.
R-value: Water Exposure.
Foam-Control PLUS+ is manufactured to resist moisture absorption in wetting conditions and release absorbed moisture quickly during drying periods, which means Foam-Control PLUS+ maintains R-value.
R-value: Water Exposure.
XPS is manufactured to resist moisture absorption in wetting conditions, but long-term in-situ testing has shown XPS traps water due to its low drying potential.  This means XPS loses R-value.
Vapor Permeance.
The vapor permeability of Foam-Control PLUS+ ranges from 2.5 to 5.0 perms for a 1 in. thick material. This is approximately 2-3 times better than XPS.
Vapor Permeance.
The vapor permeability of XPS is typically 1.5 perms for a 1 in. thick material. XPS over 1.5 in. thick will act as a vapor retarder which may trap moisture in some climate zones.
Don’t Compromise, PLUS+ insulation provides more thermal resistance (R-value) per dollar.

Selecting Comparable PLUS+ and XPS Insulations

  Foam-Control PLUS+ Compared to XPS