SKU: 16273097828

JM (Johns Manville) R-49 Unfaced Fiberglass Batt Insulation, 16 in x 48 in, 32 sq ft

Sale price$57.92 Regular price$64.36
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Description

JM (Johns Manville) R-49 Unfaced Fiberglass Batt Insulation, 16 in x 48 in, 32 sq ftR 49 Unfaced Fiberglass Batt Insulation JM R 49 unfaced fiberglass batt insulation is designed for wood framed attics, ceilings, and floors to help improve energy efficiency and reduce sound transmission. Pre cut 16 in x 48 in batts fit standard 16 in on center spacing and can be added over existing insulation where no vapor barrier is needed. Key Features: High thermal performance: R 49 fiberglass batts help reduce heat loss and improve overall

R-49 Unfaced Fiberglass Batt Insulation

JM R-49 unfaced fiberglass batt insulation is designed for wood-framed attics, ceilings, and floors to help improve energy efficiency and reduce sound transmission. Pre-cut 16-in x 48-in batts fit standard 16-in on-center spacing and can be added over existing insulation where no vapor barrier is needed.


Key Features:

  • High thermal performance: R-49 fiberglass batts help reduce heat loss and improve overall energy efficiency
  • Unfaced design: No vapor barrier—ideal for layering over existing insulation where appropriate
  • Sized for standard framing: Pre-cut 16-in x 48-in batts for 16-in on-center joist spacing
  • Added comfort: Helps provide sound control in floors/ceilings
  • Indoor air quality focused: Formaldehyde-free and GREENGUARD Gold Certified

Specifications Table:

Specification Details
Brand JM
Category Batt Insulation
R-Value R-49
Insulation Type Fiberglass
Faced/Unfaced Unfaced
Coverage Area (Sq. Feet) 32
Width (Inches) 16
Length (Inches) 48
Thickness (Inches) 13.5
R-Value per Inch 3.63
Maximum R-Value 49
Stud Spacing (Inches) 16
Framing Type Wood studs
Vapor Retardant No
Sound Barrier Yes
Formaldehyde Free Yes
ENERGY STAR Certified Yes
GREENGUARD Gold Certified Yes
Package Type Multi-pack
Package Count 6
Total Package Quantity 24
Multi-Pack Quantity 4
Bag Dimensions (L x W x D) 16.5 x 20 x 49
Package Weight (lbs.) 26.83
For Use in Attics Yes
For Use in Ceilings Yes
For Use in Floors Yes
For Use in Basements No
For Use in Crawlspaces No
For Use in Walls No
Fits 2 x 4 Walls No
Fits 2 x 6 Walls 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
CA Residents: Prop 65 Warning(s) No

Frequently Asked Questions (FAQ):

Q: Where can I use this insulation?
A: It’s intended for wood-framed attics, ceilings, and floors.


Q: Does this batt include a vapor barrier?
A: No—this product is unfaced and does not include a vapor retardant.


Q: Will it fit standard framing?
A: Yes, the batts are 16 in wide and 48 in long for 16-in on-center spacing.


Q: Can I add it over existing insulation?
A: Yes, unfaced fiberglass batts can be added to existing insulation.


Q: Is it formaldehyde-free and certified for indoor air quality?
A: Yes—Formaldehyde Free is listed as Yes, and it is GREENGUARD Gold Certified.


Quiet, cocooning comfort—layered in the bones of your home

Great design is as much about what you feel as what you see—and insulation is the invisible luxury that makes a home serene. These R-49 unfaced fiberglass batts tuck cleanly between joists, elevating comfort with warmth retention and sound-softening ease. Use them to fortify attic and ceiling planes so the rooms below feel calmer, more consistent, and effortlessly livable. It’s the kind of behind-the-scenes upgrade that makes everyday living feel truly elevated.


Upgrade your attic, ceiling, or floor cavities with JM R-49 batts for a more efficient, quieter home.

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: 16273097828

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4.2 ★★★★★
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Product Reviews
M
Verified Purchase
Matt
Lowell, US
★★★★★ 5
Great for All Cars but Especially German Cars
Size: 300 Milliliter
I use this in our used VW we bought and it helps keep the carbon build up down with their direct injection feature. I pair it with their oil additive which helps lubricate the rings so they don't stick as much.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 22, 2026
S
Verified Purchase
Sara James
Charlottesville, US
★★★★★ 5
Significant Improvement in Performance with Liqui Moly Jectron
Size: 300 Milliliter
I've been using the Liqui Moly 2007 Jectron Gasoline Fuel Injection Cleaner in my vehicle, and I am thoroughly impressed with the results. The 300 ml bottle, though compact, has made a noticeable difference in the performance of my car. After adding the Jectron cleaner to my gasoline tank, I noticed an improvement in the engine's responsiveness and smoothness within just a few drives. The idling has become steadier, and the acceleration feels more robust and refined. It's as if my car has regained a level of vitality that I hadn't realized was missing. The cleaner is incredibly easy to use – simply pouring it into the fuel tank before filling up ensures it mixes well and distributes evenly throughout the fuel system. I appreciate that this product is designed to be compatible with all gasoline engines, making it a versatile choice for different types of vehicles. One of the most significant benefits I've observed is the reduction in start-up problems and engine hesitation. It's clear that the Jectron cleaner effectively cleans the fuel injectors, improving fuel atomization and combustion efficiency. This has not only enhanced the driving experience but also contributed to better fuel economy, which is a fantastic bonus given current fuel prices. The blue color of the liquid and the design of the bottle make it easy to identify and use, ensuring I don't mix it up with other products. Despite being a single 10.14 Fl Oz pack, this cleaner packs a punch, proving that a little goes a long way. In conclusion, the Liqui Moly 2007 Jectron Gasoline Fuel Injection Cleaner has exceeded my expectations. It has revitalized my car's engine, improved fuel efficiency, and provided a smoother, more enjoyable driving experience. I highly recommend this product to anyone looking to enhance their vehicle's performance and maintain the health of their fuel injection system.
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Reviewed in the United States on February 18, 2024
P
Verified Purchase
Palmetto Dan
Houston, US
★★★★★ 5
Great fuel cleaner
Size: 300 Milliliter
Excellent fuel injection cleaner! Works great for keeping injectors clean. Improves engine performance. Easy to use. Makes a noticeable difference. Good value. Highly recommended for regular engine maintenance. Perfect product for anyone caring for their car!
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Reviewed in the United States on May 2, 2026
R
Verified Purchase
Randy W R
Bozeman, US
★★★★★ 4
Reputable, reasonably priced fuel additive to clean valves, with handy dispenser. Not all comes out.
Size: 300 Milliliter, Size: 300 Milliliter
Honest review of Liqui Moly 2007 Jectron Gasoline Fuel Injection Cleaner - 300 ml , blue @ $8.68 at time of order. I recently acquired a 2002 Ford Taurus with the 3.0L V6 and DOHC. It only had about 131,000 miles on it, but I noticed it seemed like there would be some intermittent misses in the firing. Other than oil changes, I do not believe that this vehicle was mechanically well maintained. After some research and reading reviews of products, I opted to try some injection cleaner as one step in a treatment regimen. I will endeavor to update this review with results after giving it time to work. Likes: Amazon Prime shipping, returns and refunds within 30 days of receipt. Reputable product. The price point seemed reasonable, especially if it works as advertised (10.1 ounces, single treatment can). Comes with dispensing attachment for easier pouring. Dislikes: The design of the can and pouring mechanism left a small amount of product inside the can of valve cleaner. Even completely inverting the can it wouldn’t come out. Granted, it wasn’t a whole lot, but I paid for all of it, not for some left in the can that wouldn’t even shake out. Sorry if this sounds nitpicky, but it is also a problem for disposal afterwards as it has to sit out and evaporate or put it in the trash with flammable liquid inside. Meh: I have put several miles on since adding this to just over a quarter tank of fuel and have not noticed any improvements. I realize it might take a while longer perhaps. Hopefully this honest review helps someone decide about this product.
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Reviewed in the United States on June 6, 2023
L
Verified Purchase
Logan
Alexandria, US
★★★★★ 5
Helped smooth engine idle and acceleration
Size: 300 Milliliter
Bought a new to me bmw and this stuff made it run smoother definitely helped clean things up internally car has a smoother throttle response and sounds smoother at idle will definitely be using as recommended to keep injectors and internals cleaner
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Reviewed in the United States on March 9, 2026

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