uPVC Shim Packers (or Flat Packers / Shims):

• Shape: These are typically flat, rectangular, solid plastic packers.

• Purpose: They are highly versatile and used to:

  • Glazing: The primary type of packer used for “toe and heeling” to support the glass unit’s weight within the uPVC frame, preventing it from dropping or putting stress on the frame.

  • Levelling and Spacing: Crucial for ensuring that uPVC window and door frames are installed perfectly level and plumb in the opening. They fill small gaps between the frame and the wall.

  • Aligning Components: Used to ensure various uPVC components fit together precisely and securely, eliminating play or gaps.

  • General Construction: Can also be used for other levelling tasks in construction, such as aligning kitchen cabinets, flooring, or wall studs.

• Characteristics:

  • Made of rigid uPVC or polypropylene.

  • Come in a wide range of thicknesses (also often color-coded, e.g., 1mm, 2mm, 3mm, etc.).

  • Available in various widths to match the glass unit or frame profile.

Why are U & Shim Packers Important in uPVC Installation?

• Structural Integrity: They distribute loads evenly, preventing stress concentrations that could damage the uPVC profiles or the glass.

• Smooth Operation: Correct use of packers ensures sashes open and close smoothly, and locks engage properly.

• Longevity: They prevent sagging, distortion, and premature wear of the uPVC frame and hardware.

• Airtightness & Watertightness: Proper shimming ensures the frame is true, allowing gaskets and seals to function effectively against drafts and water ingress.

• Aesthetics: They ensure a professional and aligned appearance for the finished installation.