M-D Building Products Gray Foam Backer Rod 1/2”x20’

Name: M-D Building Products Gray Foam Backer Rod 1/2”x20’
SKU: 5329883
Availability: InStock

$4.84

SKU: 5329883 Categories: Building Materials, Insulation & Weatherization

In stock

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This M-D Building Products Gray Foam Backer Rod acts as an essential “caulk saver” for filling medium-sized gaps and joints before applying sealant. The 1/2 inch diameter, closed-cell polyethylene foam is non-absorbent and flexible, designed to be pressed into cracks in sidewalks, expansion joints in driveways, window frames, and wall joints. By filling most of the space, the 20 foot length of backer rod reduces the amount of expensive caulk needed, ensures the caulk sets to the proper depth, and prevents three-point bonding for a longer-lasting seal.

Key Features of M-D Building Products Gray Foam Backer Rod

1/2 inch diameter is suitable for filling medium gaps before caulking and sealing

Acts as a "caulk saver" to significantly reduce the amount of sealant needed

Closed-cell polyethylene foam material is non-absorbent and weather-resistant

Prevents the caulk from sticking to the bottom of the joint, ensuring a two-point bond

Fills gaps to prevent drafts, moisture intrusion, dust, and insects

Flexible material can be easily cut to length with scissors for a custom fit

Recommended for use in expansion joints in concrete, pavement cracks, and wall joints

Insulates and cushions the joint, adding a layer of weatherization

Additional Information

Brand: M-D Building Products

Product Type: Foam Backer Rod

Model:

Product Use: Caulk filler and joint insulation

Size:

Material: Polyethylene Foam

Height: 1/2 inch (Diameter)

Length: 20 feet

Width: 1/2 inch (Diameter)

To install this backer rod correctly, ensure it is set to the proper depth in the joint so that the subsequent layer of caulk will be no thicker than 1/2 of the joint width and no thinner than 1/4 inch. Use a blunt tool, like a putty knife handle, to gently push the rod into the gap without puncturing the foam. This ensures the caulk has the necessary body and flexibility to cure correctly and move with the joint over time.