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Internet # 300839302

Model # C21CP

Store SKU # 1002376030

E/O 3/8 in. Dia x 350 ft. Contractor Pack Caulk Backer Rod

$31.27
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  • Closed-cell poly-foam material seals cracks for energy efficiency
  • Polyurethane construction absorbs shocks and prevents vibration
  • Foam tape allows trimming to fit the desired length
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Product Details

About This Product

The Thermwell Products 3/8 in. x 350 ft. Caulk Saver Contractor Pack helps insulate and cushion while reducing the amount of caulk needed to fill or seal large openings. Use to back fill large gaps before applying caulk (caulk sold separately). Helps insulate and cushion while reducing the amount of caulk needed to fill or seal large openings.

Highlights

  • Suitable for use with pavement, cracks, wall joints and foundations
  • Compatible with most caulks and sealants
  • Made of resilient, closed-cell poly foam for durability
  • Saves on the amount of caulk needed to fill cracks
  • Saves time and energy
  • Saves money
  • Click here to learn more about Eco Options and Energy Efficiency
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Product Information

Internet # 300839302

Model # C21CP

Store SKU # 1002376030

Specifications

Dimensions: H .375 in, W .375 in, D 4200 in

Dimensions

Product Depth (in.)

4200 in

Product Height (in.)

.375 in

Product Width (in.)

.375 in

Unspooled Length (ft.)

350

Details

Builders Hardware Product Type

Foam Tape

Color Family

Grays

Color/Finish

Gray

Density

2.0

Hardware Color Family

Gray

Interior/Exterior

Interior/Exterior

Location Type

Doors, Multi-Purpose, Windows

Material

Polyethylene

Returnable

90-Day

Single/Double

Double Sided

Warranty / Certifications

Manufacturer Warranty

90 Days

Questions & Answers

10Questions
caret
Q:My Timbertech deck howls loudly when it is windy. I was told to install backer rod between each board the entire length of the deck and not to caulk. Will this deteriorate in the hot sun and icy winters?
by|Apr 20, 2022
1 Answer
Answer This Question

A:  Yes they will decay over time. You would have to replace about every 2 years depending how much sun it gets

by|Apr 20, 2022
    caret
    Q:Can this product be used to seal dry wall gaps, under texturing material? Would it expand if wet?
    by|Mar 24, 2022
    1 Answer
    Answer This Question

    A:  I guess it could work. But it would be a hack job to use it. Backer rod is for joints that are caulked. It forces adhesion to promote flexibility within the joint so the caulking won’t tear. If you have gaps in drywall use hot mud (setting mud)to fill them. Then go back and tape. 

    by|Mar 28, 2022
      caret
      Q:Can this be used to help seal a gap between an HVAC's return box and exterior wall? I have a gap that is about a 1/2" that needs to be sealed. See attached photo. I can only access the gap from the outside. Want to install backer rod, then sealant.
      by|Nov 20, 2021
      1 Answer
      Answer This Question

      A:  Yes you could use this to help seal the gap.

      by|Nov 21, 2021
        caret
        Q:i have 29784 lf of backer Rod, How much it will be
        by|Nov 9, 2020
        1 Answer
        Answer This Question

        A:  So let's do some math. 29,784ft / 350ft (one box) = 85.097 boxes So you will need a little more than 85 boxes. 85 x $26.78 (the price of one box) = $2,276.30 total (not including tax and the extra you will need).

        by|Apr 18, 2022
          Showing 1-4 of 10

          Customer Reviews

          4.5 out of 5

          • 4.5 out of 75 reviews
          • 88% recommend this product
          Filter by:
          Showing 1-10 of 75 reviews
          We used this product during the floating floor installation in our upstairs bathroom. It provide...
          We used this product during the floating floor installation in our upstairs bathroom. It provided the necessary expansion joint of 3/8" at the wall joint. It also reduced the amount of caulking required to provide a waterproof joint. It was easily pressed into the gap between the floor and wall and cut with a putty knife.
          by
          • Pro
          • Verified Purchase
          • Recommended
          3 found this review helpful
          wrong size
          Box was mislabeled with incorrect size. I needed 3/8 inch and after I struggled with about 10 feet of the backer rod before realizing it wasn't me who measured wrong but that I was sold the wrong product as the original label shows 1/2 inch. Another home depot return.
          by
            1 found this review helpful
            It worked great for stuffing the gap at the bottom of my house, so that I could caulk the gap. I had to do waterproofing around the bottom of my house.
            by
            • Verified Purchase
            by
            • Verified Purchase
            by
            • Verified Purchase
            This material was coiled up in the box like a nest of snakes. Very hard to unpack and unravel. The product itself is very good.
            by
            • Verified Purchase
            Initially bought a 20’ section….and it was an ACTUAL 3/8” . Was very happy with that purchase so I bought another 20’….same packaging, different color and NOT 3/8”! I am using this product as a flexible filler in the gap between my drywall and the ends of my laminate planks. I needed a whole lot more of it, so ordered the contractor pack….HOPING for 3/8”! It wasn’t. My gap is EXACTLY 3/8” and the whole package had to crammed into the slit with the end of a plastic ruler! It bulged because it was so tight! Useful elsewhere, nor for flooring insulation…
            by
            • Verified Purchase
            Saves money on caulk. Good purchase.
            by
            • Verified Purchase
            by
            • Verified Purchase
            Material itself is okay. Not much to review about...
            Material itself is okay. Not much to review about foam backer rod. But the packaging was something else. Came in a neatly sealed box. When opened it revealed a den of snakes inside. The rod was haphazardly jammed into the box in a tangle and it is impossible to retrieve more than a couple of feet without unthreading it through some hidden loops.
            by
            • Verified Purchase
            Showing 1-10 of 75 reviews

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