SIP Comparison

The Bar Has Been Raised.

As the leader in the SIP panel industry, it is our responsibility to not only build a quality product but to build a product that will outperform and outlast all other insulation products under the toughest conditions.

Let's Compare Common Insulations

As with any insulation (cellulose, fiberglass, polyurethane, and polystyrene a.k.a. EPS or XPS,) as the air temperature drops the R-value increases. As the air temperature raises the R-value decreases. It is important that when you see an R-value you know at what temperature the product was tested. The apples to apples R-value ASTM C518 comparison is 75°F. The per inch R-values below are in accordance with the ASTM C518 Standards at 75°F.

*R-VALUES AT 75°F R-Value/ Inch R-Value 2x4 (3.5") R-Value 2x6 (5.5") R-Value 2x8 (7.25")
RAY-CORE Polyurethane Foam 7 24.5 38.5 50.7
Icynene Spray Foam 5.8 20.3 31.9 42.0
Extruded Polystyrene  (EPS) 5.0 17.5 27.5 36.2
Expanded Polystyrene (XPS) Avg. 4.0 14 22 29
Fiberglass Batts 3.2 11.2 17.6 23.2
Cellulose 3.5 12.25 19.2 25.3
Wet-Spray Cellulose 3.4 11.9 18.7 24.65
Blown-in Fiberglass 2.4 8.4 13.2 17.4


Compare RAY-CORE SIPs vs. Sandwich Panel SIPs

RAY-CORE Polyurethane SIP Panels
Douglas Fir Studs (12, 16, or 24 inches on center) centuries old proven structural integrity and standard framing practices and tools. No studs - OSB and glue provide the structural integrity of the panel (some manufacturers use 2x splines to connect one panel to the next).

Highest R-Value of any SIP core material (7 per inch).
Thinner walls= savings on top &asp; bottom plates, window &asp; door jamb openings.

Lowest R-Value of any SIP core material (3.6 - 4.2 per inch).
Thicker walls= increased material costs.

Integrated radiant vapor barrier on both sides prevents transfer of moisture. (.02 perm rating). No integrated vapor barrier.

Low perm rating - Impermeable (Does Not Retain Moisture)
Low moisture retention Prohibits mold growth.
No rotting.
No bacterial growth.
Studs rather than glue and OSB provide structural integrity. No moisture deterioration.

High perm rating of 3 (retains moisture).
High moisture retention Promotes mold growth.
Contributes to rotting.
Allows bacterial growth.
Moisture deterioration delaminates OSB, eliminating structural integrity.

Class 1 fire rated- ASTM E-84.
High melting point- melts at 375°F.
High fire resistance.

NOT class 1 fire rated.
Low melting point- softens at 165°F and melts at 210°F
Poor fire resistance.

No Special Engineering Required. Standard stick framing code and plan requirements.

Expensive and Extensive Special Engineering Required (this will increase building costs). Not all code jurisdictions allow the use of sandwich panel SIPs.


Only RAY-CORE combines the three advanced technologies of studs, high density closed cell polyurethane foam insulation and a radiant foil vapor barrier into one energy saving lightweight SIP panel.

More information about RAY-CORE SIP Panels.