Polycarbonate Roofing Accessories Explained: Glazing Bars, Tapes & Fixings

Polycarbonate Roofing Accessories Explained: Glazing Bars, Tapes & Fixings

When installing a multiwall polycarbonate roof, the sheets are only one part of the overall system. A complete installation requires the correct accessories to support the sheets, manage moisture, and finish the roof neatly. Using compatible components helps ensure that the roof functions as intended and maintains a consistent appearance.

This guide explains the main accessories used in polycarbonate roofing systems—glazing bars, tapes, and fixings—and outlines their typical uses.

Browse all accessories here:
👉 https://polycarbonatex.co.uk/collections/multiwall-accessories

1. Glazing Bars

What Are Glazing Bars?

Glazing bars are used to join polycarbonate sheets together and to connect them to the supporting structure. They help maintain correct spacing between sheets and create a secure connection along the roof.

Example product:
https://polycarbonatex.co.uk/collections/multiwall-accessories/products/corotherm-multiwall-polycarbonate-sheet-glazing-bar-with-1-end-cap-1

Types of Glazing Bars

Aluminium Glazing Bars

  • Provide a robust joining method

  • Often selected for larger structures such as verandas, canopies, or carports

  • Suitable for installations that require a more substantial fixing system

PVC Glazing Bars

  • Lightweight and straightforward to install

  • Commonly used for smaller roofs, lean-tos, and pergola projects

  • Easy to cut and handle for DIY applications

Why Glazing Bars Matter

Glazing bars help:

  • Support and secure the sheets

  • Create sealed joints between panels

  • Maintain consistent sheet alignment

Always match glazing bar size to the correct sheet thickness (e.g., 10mm bars for 10mm sheets).

Explore glazing bars here:
👉 https://polycarbonatex.co.uk/collections/multiwall-accessories

2. Polycarbonate Tapes

Why Tapes Are Important

Multiwall polycarbonate sheets contain open internal chambers that require correct sealing. Tapes help prevent dust and debris entering these chambers and allow moisture to ventilate where appropriate.

Types of Polycarbonate Tape

Aluminium (Solid) Tape

  • Applied to the top edge of the sheet

  • Creates a sealed barrier to help prevent water and debris entering the flutes

Breather (Vented) Tape

  • Applied to the bottom edge

  • Allows controlled ventilation while blocking dirt, insects, and debris

Examples:
Breather tape – https://polycarbonatex.co.uk/collections/multiwall-accessories/products/corotherm-multiwall-polycarbonate-sheet-breather-tape-10m

Common Taping Considerations

  • The top edge uses solid tape

  • The bottom edge uses breather tape

  • Correct taping contributes to maintaining a clear appearance inside the sheet chambers

3. Fixings for Polycarbonate Roofing

What Are Polycarbonate Fixings?

Polycarbonate sheets expand and contract naturally with temperature changes. Purpose-made fixings help secure the sheet while allowing for this movement.

Common Fixing Options

Screw, Spacer & Cap Systems

  • Designed to fit over pre-drilled holes

  • Include spacers to prevent overtightening

  • Typically supplied with cover caps for a neat finish

Super Fixing Buttons

  • Used when sheets are fixed directly to timber or metal

  • Help distribute load around the fixing point

Example:
https://polycarbonatex.co.uk/collections/multiwall-accessories/products/corotherm-multiwall-polycarbonate-sheet-super-fixings-buttons-pack-of-10

Best Practice for Fixing Polycarbonate

  • Pre-drill holes slightly larger than the fixings to allow for movement

  • Do not overtighten

  • Only use fixings designed for multiwall polycarbonate

Additional Accessories for Finishing a Polycarbonate Roof

Depending on the installation, you may also require:

These components support weather protection and help achieve a neat, finished appearance.

Why Correct Accessories Matter

Using accessories designed for multiwall polycarbonate systems helps ensure:

  • Sheets are supported and aligned correctly

  • Open chambers are sealed appropriately

  • Fixings allow natural movement

  • Edges and joints are finished neatly

Choosing compatible components is an important part of creating a complete roofing system.

Browse Polycarbonate Roofing Accessories

polycarbonatex.co.uk supplies glazing bars, tapes, fixings, end closures, and other components designed for multiwall polycarbonate roofing systems.

👉 View the full accessories range here:
https://polycarbonatex.co.uk/collections/multiwall-accessories

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