PEF Backer Rod

Description

PEF closed cell backer rod is manufactured in New Zealand, from high quality closed cell, Low Density Polyethylene foam. It is a circular joint backing material, primarily for use in conjunction with elastomeric sealants.

Backer rod must be rolled into joint gaps at a consistent depth to form a firm base for controlling the application thickness of gun applied elastomeric sealant. Backer rod is used for forming the base of vertical and horizontal joints typically found in the following applications:

• Joints between precast concrete panels
• Expansion joints between bricks and masonry
• Saw cut joints in concrete floors
• Backing for joints and changes in direction in tiled surfaces
• Around penetrations through walls and floors
• Perimeter joints around timber and aluminium windows and doors
• As draught or dust proofing stop in applications where elastomeric sealing is not required

CHARACTERISTICS

• Weather resistant*
• Closed cell – no water absorption
• Sealants do not adhere to PE foam
• Allows sealant to adhere on 2 faces so sealant has unrestricted movement
• Nontoxic, suitable for applications in food preparation areas
• Easy to install
• Wide range of sizes available
• Resistant to most chemicals
• Easily compressible, good rebound expansion
• Extremely light weight

APPLICATION INSTRUCTIONS

PEF Rod should be selected to have a diameter 25-30% greater than the width of the joint being filled, this ensures it remains in place during sealant application.

When installing PEF backer rod, it is essential that a rounded edge tool is used, this avoids cutting or puncturing the foam surface. Puncturing of the backer rod’s waxy surface can cause ‘off gassing’ that may lead to bubbles appearing in the uncured sealant. Any section of backer rod damaged during installation should be replaced. Using a backer rod application tool is strongly recommended.

The rod must be positioned to achieve a uniform predetermined depth from the proposed sealants surface, without twisting, gaps, or undulations in the surface. During installation avoid excessive stretching of the rod, this reduces the rod’s diameter and therefore compression in the sides of the joint.

Refer to the sealant provider’s guide, regarding information on joint design and calculation of joint movement.