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Deal.ai › Guardian Building Products › Energy efficient
Guardian Building Products
Guardian Building Products 302646 24 x 28 in. Insul Batt R38k

Guardian Building Products 302646 24 x 28 in. Insul Batt R38k

4.9(48 ratings)

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$180.30at WalmartChecked Nov 14

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Price facts

  • Last seen at $180.30 at Walmart on Nov 14.

Our take on the Guardian Building Products 302646 24 x 28 in. Insul Batt R38k

This is a single fiberglass batt, 24 by 28 inches, rated R38 for high-resistance thermal performance in ceilings and tight attic spaces. It is formaldehyde-free and carries Asthma & Allergy Friendly and Verified Healthier Air certifications, which no other fiberglass insulation line holds. The 24-inch width suits wider joist spacing than standard 16-inch batts, so fewer pieces cover the same area. Owners rate it highly for easy cutting, low dust and quick recovery from the pack.

Best forAttics and ceilings needing high R-valueHomes with 24-inch joist or stud spacingDIY installers who want low-dust, low-odor insulationAllergy-sensitive households
Pros
  • R38 rating gives strong thermal resistance for cold and hot climates
  • Formaldehyde-free binder and low VOC emissions
  • Asthma & Allergy Friendly and Verified Healthier Air certified
  • Cuts cleanly and recovers quickly from compression
  • Low dust after installation
  • Adds acoustical insulation as well as thermal
Cons
  • Sold as a single batt, so large jobs need many pieces
  • 24-inch width does not fit standard 16-inch framing without trimming
  • Fiberglass still requires gloves, long sleeves and a mask
  • R38 is bulky and awkward in tight attic spaces

Guardian Building Products 302646 24 x 28 in. Insul Batt R38k prices at every store

  • WalmartNew

    In stockSold by Supply the HomeReturns: Sold by a Walmart Marketplace seller; returns go to the seller under the seller's returns policy.

    $180.30Free shippingChecked Nov 14
    Visit Walmart

What reviewers say

  • 4.9 / 548 ratings

Buyers rate it 4.9 out of 5 and mostly praise handling: it cuts cleanly, springs back after unpacking and leaves little dust. The allergy and air-quality certifications come up as a reason to choose it over ordinary fiberglass.

What people mention
  • HandlingPraisedReviewers say it cuts cleanly and installs easily for both pros and DIYers.
  • DustPraisedBuyers note very little dust after installation compared with other fiberglass.
  • RecoveryPraisedOwners report the batts spring back to full thickness quickly after unpacking.
  • Odor and air qualityPraisedThe formaldehyde-free binder and low emissions are cited as reasons to buy.
  • QuantityCriticisedSome buyers find one batt goes a short way on larger jobs.

About the Guardian Building Products 302646 24 x 28 in. Insul Batt R38k

This is a fiberglass insulation batt in the Knauf line, sold under the Guardian Building Products name. It acts as a thermal barrier in both hot and cold climates, which can lower energy use and bills. It also provides acoustical insulation and helps make a home or commercial structure more comfortable indoors.

Knauf Performance+ products are Asthma & Allergy Friendly Certified and Verified Healthier Air. The certification program was established by the AAFA and Allergy Standards Limited (ASL). It involves physical and chemical testing to confirm that products reduce allergen exposure and limit indoor pollutants.

Knauf's residential Performance+ insulation has a formaldehyde-free binder. It leaves extremely low dust levels after installation. It also has extremely low VOC emissions at 24 hours and at 14 days after installation.

Brand
Guardian Building Products
Model
302646
Size
24 in. x 28 in.
Insulation type
Fiberglass batt
Certifications
Asthma & Allergy Friendly Certified; Verified Healthier Air (Performance+ products)
Binder
Formaldehyde-free (residential Performance+)
Uses
Thermal and acoustical insulation for homes and commercial structures

Specifications

color
MulticolorSource
size
24" x 28"Source

Questions and answers

What does R38 mean?
R38 is the thermal resistance rating. Higher R-values resist heat flow better, and R38 suits ceilings and attics in most climates.
Will it fit 16-inch joists?
It is 24 inches wide, sized for wider framing. On 16-inch spacing you will need to trim it to fit.
Is it safe for allergy sufferers?
It is formaldehyde-free and certified Asthma & Allergy Friendly with low dust and low VOC emissions. Wear gloves and a mask during installation regardless.
Can I install it myself?
Yes. It is made for DIY handling: it cuts with a utility knife and needs no special tools beyond safety gear.
Does it help with sound?
Yes. Fiberglass batts also provide acoustical insulation, damping sound between rooms and from outside.
How many batts do I need?
Each batt covers 24 by 28 inches. Measure your area and divide to get the count, adding a little for cuts and waste.
Where is the Guardian Building Products 302646 24 x 28 in. Insul Batt R38k cheapest?
At Walmart, for $180.30, as of our latest check.
What do buyers say about the Guardian Building Products 302646 24 x 28 in. Insul Batt R38k?
Rated 4.9 out of 5 from 48 ratings.

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