40mm Flat Glazing Packers

40mm Flat Glazing Packers are wide-format plastic packers designed for glazing applications where installers need a larger support footprint beneath the glass unit.

Measuring 40mm x 100mm, FP40 packers offer one of the widest flat packer profiles in this range. This makes them particularly useful for wider glazing rebates, larger sealed units, door systems, conservatories, and curtain walling work where a broad and stable bearing surface is preferred.

Made from durable polypropylene, these packers provide firm support under load and help keep units correctly positioned during installation. Their rigid construction also makes them suitable for repeat trade use where accurate spacing and consistent thickness are important.

Why installers choose 40mm Flat Glazing Packers:

• 40mm wide profile for maximum flat packer contact area
• Suitable for very wide glazing channels and larger glazed units
• Helps create a stable base beneath sealed units
• Useful for levelling, spacing, lifting, and unit positioning
• Durable polypropylene material resists moisture and compression

These 40mm glazing packers are a strong choice when smaller packers do not provide enough surface area and the installation needs a wider, more stable support point.

What Each Thickness is Used For

1mm – Final Alignment & Small Height Changes

Used where only a very small adjustment is needed to complete the installation.

Best for:

• Final unit alignment
• Fine height correction
• Small gap adjustment
• Layering with thicker packers for precise spacing

2mm – Light Packing & Controlled Spacing

Useful for small corrections in wide glazing channels.

Best for:

• Minor levelling work
• Light support under sealed units
• Small spacing corrections
• Fine adjustment during fitting

3mm – General Wide-Packer Support

A practical thickness for everyday glazing tasks where a wider packer is preferred.

Best for:

• Standard unit support
• General window and door fitting
• Routine spacing work
• Building up height with multiple packers

4mm – Medium Gap Filling

Used when the unit or frame section needs a more noticeable lift.

Best for:

• Moderate gap correction
• Levelling larger sealed units
• Supporting units in wider rebates
• General trade glazing applications

5mm – Larger Lift & Stronger Base Support

Provides extra height and firmer support for larger or heavier units.

Best for:

• Bigger installation gaps
• Heavier sealed units
• Door and conservatory work
• Base support before final fixing

6mm – Maximum Thickness for Bigger Adjustments

Used when the installation requires the thickest FP40 option for firm, stable packing.

Best for:

• Deep gaps beneath glazed units
• Heavy-duty support points
• Large window or door systems
• Raising units to the correct fitted position