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FOAMULAR® & FOAMULAR® NGX™ C-300 XPS | Foam Board Insulation | Owens Corning Insulation Skip to Main Content

WHY CHOOSE FOAM BOARD INSULATION?

Owens Corning® FOAMULAR® NGX® C-300 Extruded Polystyrene (XPS) Insulation is a closed-cell, moisture-resistant rigid foam board well suited to meet the needs of a wide variety of building applications.1 Great for above-and below-grade residential and commercial applications such as wall assemblies and under slab (≤ 30 psi).

1 Not for use in flat or low slope roofing. For low slope roofing applications, use FOAMULAR® C-200 NGX® or FOAMULAR® NGX® 400/600/1000 Extruded Polystyrene (XPS) Rigid Foam Insulation.
Warning: This video contains flashing images that could trigger seizures for people with photo sensitivity.

Basic Uses/Related Uses

  • Under slabs (≤ 30 psi)
  • Perimeter/Foundation walls

Selection Criteria

  • Moisture resistant (hydrophobic), long term durability
  • Function as air and weather barrier with sealed joints
  • Compatible with common liquid or sheet applied air/moisture barriers
  • Saw, cut, or score to size
  • Reduces thermal bridging

Certifications and Sustainable Features

  • Certified by SCS Global Services to contain a minimum of 20% recycled content pre-consumer #SCS-RC-01132.
  • GREENGUARD Certified products are certified to GREENGUARD standards for low chemical emissions into indoor air during product usage. For more information, visit ul.com/gg.
  • Environmental Product Declaration (EPD) has been certified by SCS Global Services. EPD #SCS-EPD-09753.
  • UL CERTIFIED — See Bulk Shipment Certificate U-197 available at owenscorning.com/U197.
  • Contributes to credits in green building programs such as LEED® and Green Globes. For further information see documents: LEED® v4 for Building Design and Construction and Owens Corning Impact Study - Leadership in Energy and Environmental Design (LEED® v4).

Performance Attributes

SUPER MOISTURE RESISTANCE

DURABLE

EASY TO CUT, FORM & FIT

80% GLOBAL WARMING REDUCTION*

* Impact measured over 100-year time horizon, as compared to legacy FOAMULAR® insulation. EPD can be found in the Environmental and Sustainability section.

Resources

Product Focus: Owens Corning® FOAMULAR® NGX® Insulation
FOAMULAR® 101
Training Animation - ComfortShield™
Owens Corning® ComfortSHIELD™ High Performance Building Enclosure System

Technical Information

Performance Criteria

PROPERTY

VALUE

TEST METHOD

COMPLIANCE

CCMC Evaluation Listing No. 13430-L
Type 4

CCMC
CAN/ULC-701.1-17

Additional Performance Information

PROPERTY

VALUE

TEST METHOD

PHYSICAL PROPERTIES:

Compressive Strength2: 30 psi (210 kPa)

ASTM D1621

Compressive Modulus: 1350 psi (9308 kPa)

ASTM D1621

Flexural Strength2: 75 psi (517 kPa)

ASTM C203

Dimensional Stability, Maximum, % linear change: 1.5

ASTM D2126

Linear Coefficient of Thermal Expansion:
3.5x10⁵ in/in./°F (6.3x10⁵ mm/mm/°C)

ASTM E228

THERMAL RESISTANCE1:

RSI, °C•m2/W (R-Value, hr•ft2•°F/Btu)
5.0 (0.88) @ 24 °C (75 °F) mean temperature
5.4 (0.95) @ 4.4 °C (40 °F) mean temperature
5.6 (0.99) @ -3.9 °C (25 °F) mean temperature

ASTM C518 or C177

LTTR: (Canada)

Min. LTTR RSI (m2 °C/W)
RSI: 0.86 @ 25.4 mm thickness
RSI: 1.28 @ 38.1 mm thickness 
RSI: 1.70 @ 50.8 mm thickness
RSI: 2.13 @ 63.5 mm thickness
RSI: 2.59 @ 76.2 mm thickness
RSI: 3.05 @ 88.9 mm thickness
RSI: 3.52 @ 101.6 mm thickness

CAN/ULC-S770-15

MOISTURE:

Water Absorption,
(max % by volume): 0.40
(max % by volume): 0.30

ASTM D2842
ASTM C2724

Water Vapour Permeance: > 0.54 Perm (31 ng/Pa.s.m²)

ASTM E96

Water Capillarity: None

Water Affinty: Hydrophobic

Limiting Oxygen Index, min.: 24

ASTM D2863

FIRE:

CombustibleCAN/ULC-S114
Max. Service Temp. 74 °C (165 °F)

Flame Spread 190, Smoke Developed > 500

CAN/ULC-S102.2

  1. The R-value for FOAMULAR® NGX® XPS Insulation is provided from testing at mean temperatures of: -3.9 °C (25 °F), 4.4 °C (40 °F), and 24 °C (75 °F) and aging techniques of 180-day real time aged (as mandated by ASTM C578).
  2. Values at yield or 10% deflection, whichever occurs first.
  3. Value at yield or 5%, whichever occurs first.
  4. Per method described in ASTM C578

Availability

PRODUCT

THICKNESS

WIDTHS

LENGTHS

EDGES

FOAMULAR® NGX®
C-300 XPS^

25 mm - 102 mm
(1" - 4") in 12.7 mm 
(½") increments

610 mm 
(24")

2438 mm 
(96")

Square or
Ship Lapped

FOAMULAR® NGX® C-300 is shipped in units containing four individually shrink-wrapped packages. ^Metric sizes for CMU also available

Technical Information

  • Deliver FOAMULAR® NGX® XPS insulation products in their original factory-wrapped packaging.
  • Exposure to exterior conditions during normal construction cycles is permitted. During that time some fading of color may begin due to UV exposure, and, if exposed for extended periods of time, some degradation or “dusting” of the polystyrene surface may begin. It is best if the product is covered within 60 days to minimize degradation. Once covered, the deterioration stops, and damage is limited to the thin top surface layers of cells. Cells below are generally unharmed.
  • Prior to use of adhesives, sealants or other similar products with polystyrene boards, verify their compatibility with adhesive manufacturers.
  • Caution: This product is combustible. A protective barrier or thermal barrier is required as specified in the appropriate building Code. Do not expose to open flames or any other ignition source during transport, handling, storage or use. A protective barrier or thermal barrier is required to separate this product from interior living or conditioned spaces as specified in the appropriate building code.
  • Carefully adjust insulation boards to obtain tight joints between each board and around electrical service boxes, piping, air ducts and framing passing through; where two layers are required it is preferable to offset all joints. Consult an Owens Corning Canada Technical representative for appropriate fastener and adhesive selections.


Technical Services Available

For Canadian Technical inquiries, please contact our technical team at owenscorning.ca/contacttech.


Limited Warranty

FOAMULAR® NGX® XPS insulation limited lifetime warranty maintains 90% of its R-value for the lifetime of the building and covers all CAN/ULC-S701 properties. See FOAMULAR® NGX® Extruded Polystyrene Insulation Lifetime Limited Warranty for complete details, limitations, and requirements.


Environmental and Sustainability

Owens Corning is a worldwide leader in building material systems, insulation, and composite solutions, delivering a broad range of high quality products and services.

Owens Corning is committed to driving sustainability by delivering solutions, transforming markets, and enhancing lives. More information can be found at owenscorning.ca or owenscorninglibrary.ca.

FOAMULAR® NGX® XPS insulation uses blowing agents with zero ozone depletion potential.

Detailed environmental information on the lifecycle of this product can be found in product's Environmental Product Declaration.


Disclaimer of Liability
Technical information contained herein is furnished without charge or obligation and is given and accepted at recipient’s sole risk. Because conditions of use may vary and are beyond our control, Owens Corning makes no representation about and is not responsible or liable for the accuracy or reliability of data associated with particular uses of any product described herein. SCS Global Services provides independent verification of recycled content in building materials and verifies recycled content claims made by manufacturers. For more information, visit SCSglobalservices.com.
LEED® is a registered trademark of the U.S. Green Building Council.

Notes
For additional information, refer to the Safe Use Instruction Sheet (SUIS) found in the SDS Database via sds.owenscorning.com.
Certification Logos

Applications

  • Basements
  • Foundations
  • Foundations > Slab

Contact Us

Even though we're a global company, we're always ready to answer your questions. Call to speak with an Owens Corning representative.