Common Polycarbonate Roofing Mistakes (And How to Avoid Them)
Multiwall polycarbonate sheets are widely used for pergolas, canopies, garden rooms, walkways, and similar outdoor structures. While the material is straightforward to work with, many issues that occur after installation are typically related to incorrect fixing methods, unsuitable accessories, or missing components rather than the sheets themselves.
This guide outlines common installation mistakes and practical steps that can help support a suitable and long-lasting polycarbonate roof installation.
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1. Not Allowing for Thermal Expansion
The Issue - Polycarbonate naturally expands and contracts with temperature changes. If the sheets are fixed too tightly, or holes are drilled too small, the material may have limited room to move.
How to help avoid it
These steps support natural movement during temperature changes.
2. Using Incorrect Fixings
The Issue - Standard screws are not designed for multiwall polycarbonate. Using them can place excessive pressure around fixing points.
How to help avoid it
Appropriate fixings help support a secure and consistent installation.
3. Incorrect or Missing End Tapes
The Issue - The internal flutes of multiwall sheets must be sealed correctly. Incorrect taping can allow dust or debris to enter.
How to help avoid it
Correct taping supports ventilation and helps prevent contamination inside the flutes.
4. Installing Sheets with the Wrong Side Facing Outwards
The Issue - Polycarbonate roofing sheets have a UV-protected surface. Installing the sheet with the wrong side outward can reduce its effectiveness.
How to help avoid it
Correct orientation ensures the sheet is installed as intended.
5. Using Glazing Bars That Don’t Match Sheet Thickness
The Issue - Glazing bars must be the correct size for the sheet thickness. Using mismatched components may affect sheet alignment and sealing.
How to help avoid it
Appropriate glazing bars help support sheet edges and joints.
6. Insufficient Roof Pitch
The Issue - A roof that is too flat may experience slow water run-off and increased debris collection.
How to help avoid it
Adequate pitch helps support cleaner water run-off.
7. Unsupported or Excessively Overhanging Sheet Edges
The Issue - Polycarbonate sheets require suitable support along the structure. Unsupported edges may be prone to movement in certain weather conditions.
How to help avoid it
Correct support helps maintain consistent alignment across the roof.
8. Incorrect Cutting Techniques
The Issue - Unsuitable cutting tools can cause uneven edges or rough cuts, making installation more difficult.
How to help avoid it
Clean edges help ensure a neat installation.
SUMMARY
Polycarbonate roofs can be installed effectively when the correct components and techniques are used. Many common issues relate to:
Following these principles helps ensure that the sheets and accessories function as intended.
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polycarbdirect.co.za supplies multiwall polycarbonate sheets and accessories suitable for roofing systems, including glazing bars, tapes, closures, and fixings.
