Owens Corning FOAMULAR 400 (40 PSI) R-15 Extruded Polystyrene Foam Board Insulation, 3 in x 4 ft x 8 ft, Square Edge
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
Save 10%

Shipping Estimate
USA
  • USA
  • CAN

Ships within 48 hours · Estimated delivery Jul 7 - Jul 12

Promo Codes Available:

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

Discover Niche Categories That Outsell

Top-Converting Item to Boost Your Average Order

4.7 ★★★★★
Based on 711 reviews
Sort
Highest Rating
Newest First
Oldest First
Product Reviews
M
Verified Purchase
Ms. Rea
New York, US
★★★★★ 5
It's perfect support.
Size: Extra Back Support (21-Inch), Color: Dark Grey
The best way to describe the super comfy reading pillow is super comfy. I use it to sit up while watching something soothing to my mind on tv and due to its comfyness and softness, it's perfectly just right for my back. The funny thing is within a few minutes I'm knocked out sleep, which is a good thing. It's soft but firm lumbar area and arms feels oh so comfortable. It gives the best sleep quality and less toss and turning. I highly recommend.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 7, 2026
M
Verified Purchase
Michael Simko
New York, US
★★★★★ 4
Great Size and Comfort
Size: Extra Back Support (21-Inch), Color: Dark Grey
2 months after buying a different reading pillow I felt it was time to buy a different one based on the comfort and support. I found this one listed for a good price. After carefully looking through the listing, I bought the 21" size. On my first night of usage, I was already impressed with the comfort and support vs the reading pillow I had bought 2 months prior. I like how this one has nice support for my neck and head as I'm relaxing on my bed with my laptop and phone. The texture of the filling gives it a very nice combination of cushioning and firmness. The horizontal feature line in the center of the pillow is a nice feature for back and neck support thanks to it giving the pillow some flexibility. As for the arms, their length, width, height, and cushioning are very good for resting my arm while I'm using the wireless mouse with my laptop.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on February 27, 2026
G
Verified Purchase
GhostFingersXP
Louisville, US
★★★★★ 5
Book Reading Wife Approved
Size: Standard (18-Inch), Color: Sage Green
I purchased this for my wife who reads quite a bit and she absolutely loves it. She said it feels soft, is the right size for her, and makes book reading more comfortable for her. I call it a win.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 23, 2026
A
Verified Purchase
A Brown
Waukegan, US
★★★★★ 3
Not good quality
Size: Standard (18-Inch), Color: Dark Grey
Comfy, however it’s getting flat an only had it a week
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 27, 2026
L
Verified Purchase
Linda F. Del Valle
Port Orchard, US
★★★★★ 5
Love this ❤️❤️
Size: Standard (18-Inch), Color: Rose Pink
Love love super comfy soft yet firm Great quality good value the material is sturdy
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on June 3, 2026

recommand products