SKU: 65548730391

Johns Manville (JM) R-38 Unfaced Fiberglass Batt Insulation, 16 in x 48 in, 42.66 sq ft

Sale price$134.24 Regular price$149.16
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Description

Johns Manville (JM) R-38 Unfaced Fiberglass Batt Insulation, 16 in x 48 in, 42.66 sq ftR 38 Unfaced Fiberglass Batt Insulation (16 in x 48 in) JM (Johns Manville) R 38 unfaced fiberglass batts are pre cut for 16 in on center wood framing to help improve thermal performance and add sound control in attics, ceilings, and floors. Unfaced construction has no vapor barrier, making it suitable for adding over existing insulation where permitted. Key Features: High R Value Performance: R 38 fiberglass batts help reduce heat transfer for

R-38 Unfaced Fiberglass Batt Insulation (16 in x 48 in)

JM (Johns Manville) R-38 unfaced fiberglass batts are pre-cut for 16-in on-center wood framing to help improve thermal performance and add sound control in attics, ceilings, and floors. Unfaced construction has no vapor barrier, making it suitable for adding over existing insulation where permitted.


Key Features:

  • High R-Value Performance: R-38 fiberglass batts help reduce heat transfer for improved comfort and energy efficiency.
  • Unfaced for Flexible Use: No vapor barrier, so it can be added to existing insulation where appropriate.
  • Sized for Standard Framing: Pre-cut 48-in length and 16-in width fits 16-in on-center wood framing bays.
  • Sound Control Added: Built-in sound barrier helps reduce noise transmission between spaces.
  • Durable, Moisture-Resistant Material: Won’t rot, mildew, or deteriorate and is noncorrosive to pipes, wiring, and metal components.

Specifications Table:

Specification Details
Brand JM
Category Batt Insulation
Insulation Type Fiberglass
Maximum R-Value R-38
Faced/Unfaced Unfaced
Width (Inches) 16
Length (Inches) 48
Thickness (Inches) 13
Coverage Area (Sq. Feet) 42.66
Sound Barrier Yes
Vapor Retardant No
Formaldehyde Free Yes
ENERGY STAR Certified Yes
GREENGUARD Gold Certified Yes
Framing Type Wood studs
Stud Spacing (Inches) 16
R-Value per Inch 2.923
For Use in Attics Yes
For Use in Ceilings Yes
For Use in Floors Yes
For Use in Walls No
For Use in Basements No
For Use in Crawlspaces No
For Use in Doors No
For Use in Duct No
For Use in Electrical No
For Use in Garage Doors No
For Use in Masonry No
For Use in Plumbing No
For Use in Vents No
For Use in Windows No
Fits 2 x 4 Walls No
Fits 2 x 6 Walls No
Will not rot, mildew or deteriorate Yes (as described)
Noncorrosive to pipes, wiring and metal studs Yes (as described)
Package Type Multi-pack
Total Package Quantity 32
Package Count 8
Multi-Pack Quantity 4
Bag Dimensions (L x W x D) 16.5 x 20 x 50
Package Weight (lbs.) 22
Warranty 1-year limited
UNSPSC 11162400

Frequently Asked Questions (FAQ):

Q: Where can I use these batts?
A: Designed for wood-framed attics, ceilings, and floors; not listed for walls, basements, or crawlspaces.


Q: Can I install unfaced insulation over existing insulation?
A: Yes—unfaced batts can be added to existing insulation because they do not include a vapor barrier.


Q: What framing size does it fit?
A: It’s sized for 16-in on-center wood framing and comes in 48-in long batts.


Q: Does it include a vapor retarder?
A: No—this product is unfaced and has no vapor retardant.


Q: Does it help with noise?
A: Yes—this product is listed as having a sound barrier for sound control.


Quiet, cocooning comfort—layered into your home’s architecture

There’s a kind of luxury that isn’t loud—it’s felt in the calm of a perfectly tempered room and the hush that settles over a space. These R-38 unfaced fiberglass batts disappear into the structure, adding warmth, acoustic softness, and an effortless sense of ease overhead in attics and across ceilings and floors. I love the pre-cut, standard-bay sizing—clean lines, minimal fuss, maximum impact. Consider it the invisible foundation for living beautifully: comfort, control, and quiet—always in style.


Upgrade your attic or ceiling with JM R-38 unfaced fiberglass batts for better comfort, quieter spaces, and improved efficiency.

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: 65548730391

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MLG
Omaha, US
★★★★★ 5
Good watch at a good price
Color: White/Silver-Tone/Digital
Timex watches are reliable. This model was well priced, easy to clean, and keeps good time.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 18, 2026
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Nicole
Pawtucket, US
★★★★★ 5
Instructions for Timex 33mm Watch
Color: Blue/Silver-Tone/Digital, Color: Blue/Silver-Tone/Digital
Watch is good. No instructions included so I found some and posted them above. Bought this for 10yr old and fits perfectly.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on February 24, 2026
R
Verified Purchase
Rose Hilsinger
West Palm Beach, US
★★★★★ 5
Watch
Color: Black/Silver-Tone/Digital
Keep good time. I used this when I was working.
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Reviewed in the United States on April 26, 2026
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Verified Purchase
TC
Whiting, US
★★★★★ 1
A waste
Color: White/Silver-Tone/Digital
If I could I would give it zero stars. It was running when I received it so who knows how long the battery has left. No instructions were included. The setup is impossible unless you’re into computerized “smart” crap. I looked up how to do that and it’s way too involved for a watch to tell me what the time is. I don’t want a personal dictator, I just wanted a watch I could wear and know what time it is. Too much hassle to return. It’s going in the trash. Total waste of time energy and money. Zero stars.
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Reviewed in the United States on July 12, 2025
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Verified Purchase
Kristi J Williams
Pawtucket, US
★★★★★ 4
Favorite Watch
Color: Black/Silver-Tone/Digital, Color: Black/Silver-Tone/Digital
I have been using this same kind of watch for 10+ years. I like the belt like strap and the small size. I also appreciate how it has a light on it, the date, and the stop watch. I haven’t had any issues with the battery. These watches have held up well for me although I try to avoid getting them wet. The buttons are hard to press when you first get them but get a little easier to press over time. I still have issues remembering how to change the time and typically have to look up how. The silver parts on the front do wear out over time and turn copper colored. I wore one of these watches for around 5 years before buying a new one when the band which holds the excess space from the band broke. Attached is a picture of the watch that I wore for at least 5 years and a brand new one that I bought.
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Reviewed in the United States on April 11, 2026

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