SKU: 24727758219

Owens Corning FOAMULAR 400 (40 PSI) R-15 Extruded Polystyrene Foam Board Insulation, 3 in x 4 ft x 8 ft, Square Edge

Sale price$172.35 Regular price$191.50
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Ships within 48 hours · Estimated delivery Aug 13 - Aug 18

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For Your Every Summer RSVP, with Code: SUMMER15

Description

Owens Corning FOAMULAR 400 (40 PSI) R-15 Extruded Polystyrene Foam Board Insulation, 3 in x 4 ft x 8 ft, Square EdgeFOAMULAR 400 R 15 XPS Foam Board, 3" x 4' x 8' High performance extruded polystyrene (XPS) foam board delivering R 15 insulation in a durable 3 inch panel. Designed for high load applications and exterior sheathing, it resists moisture and is easy to cut and install. Key Features: High Compressive Strength: 400 series XPS rated at 40 PSI for demanding applications Moisture Resistant: Low water absorption helps retain R value over time Energy

FOAMULAR 400 R-15 XPS Foam Board, 3" x 4' x 8'

High-performance extruded polystyrene (XPS) foam board delivering R-15 insulation in a durable 3-inch panel. Designed for high-load applications and exterior sheathing, it resists moisture and is easy to cut and install.


Key Features:

  • High Compressive Strength: 400 series XPS rated at 40 PSI for demanding applications
  • Moisture Resistant: Low water absorption helps retain R-value over time
  • Energy Efficient: R-5 per inch delivers R-15 in a 3-inch board
  • Easy to Work With: Lightweight panels cut cleanly with basic tools
  • Versatile Use: Suitable for exterior foundation walls, sheathing, cavity walls, and commercial projects

Specifications Table:

Specification Details
Series Name FOAMULAR NGX F-400
Actual Length (Feet) 8
Actual Thickness (Inches) 3
Actual Width (Feet) 4
Common Length (Feet) 8
Common Thickness (Inches) 3
Common Width (Feet) 4
Coverage Area (Sq. Feet) 32
Package Weight (lbs.) 15.1
Faced/Unfaced Unfaced
Fire Resistant No
For Use in Walls Yes
For Use on Wood Yes
Formaldehyde Free Yes
Insulation Type Polystyrene (XPS)
Maximum R-Value 15
Mold Resistant Yes
Package Quantity 1
R-Value per Inch 5
Sound Barrier No
Use Location Outdoor
Vapor Retardant No
Water Resistant Yes
ENERGY STAR Certified Yes
GREENGUARD Gold Certified Yes
Warranty Limited lifetime
Compressive Strength 40 PSI

Frequently Asked Questions (FAQ):

Q: Can this board be used below grade or under slabs?
A: Yes—FOAMULAR 400 is intended for high-load applications including exterior foundation walls and under slabs; follow local codes.


Q: Does it come faced or unfaced?
A: Unfaced XPS foam board.


Q: What are the exact dimensions and coverage?
A: Each board is 3 in thick, 4 ft wide, and 8 ft long, covering 32 sq ft.


Q: Is it mold or mildew resistant?
A: Yes, XPS construction provides mold and mildew resistance.


Q: What is the R-value?
A: R-15 total (R-5 per inch).


Sculpted Strength Meets Sleek Thermal Performance

This streamlined pink panel brings architectural confidence to utility spaces, sealing envelopes with crisp, modern precision. The 3-inch profile and square edges create a clean, continuous plane that elevates foundations and sheathing alike. Pair it with exposed concrete and black hardware for an industrial-chic moment that’s as functional as it is refined. It’s an essential layer for luxurious comfort and enduring efficiency.


Upgrade your envelope with FOAMULAR 400 and lock in long-lasting R-15 performance—add to cart today.

Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 24727758219

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Joseph Pratt
Chelsea, US
★★★★★ 5
Great product.
Size: Small, Color: (001) Black / Black / White
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Reviewed in the United States on May 16, 2026
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Chelsey Bartoli
New York, US
★★★★★ 5
Great buy!
Size: Medium, Color: (001) Black / Black / White
My husband loves these. The socks are warm and thick and extremely comfortable. They support the foot and he works outside all day and has had them for a little over a month. They stay in place and don’t move move around while he’s outside moving around.
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Reviewed in the United States on November 6, 2025
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Cathy
Bozeman, US
★★★★★ 5
Happy Customer
Size: Medium, Color: (001) Black / Black / White
Item was as describe, comfortable and stays in place thick but breathable ! I will order from this company again
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Reviewed in the United States on January 15, 2026
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Verified Purchase
Sue M
Belleville, US
★★★★★ 5
Love these socks
Size: Large, Color: (035) Steel / White / Black
Great quality socks
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Reviewed in the United States on April 26, 2026
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Kendra
Battle Creek, US
★★★★★ 4
Good quality
Size: Large, Color: (035) Steel / White / Black
These are a bit thicker then a compression sock and they come up higher on the ankle than a no-show sock normally does. They are very comfortable and soft.
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Reviewed in the United States on February 10, 2026

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