Multiwall Polycarbonate Glazing Sheet

6mm Twinwall Corotherm

6mm Twinwall Corotherm is a light weight, impact resistant polycarbonate roofing and glazing sheet.  It is guaranteed for 10 years.


  • Available in clear for maximum light transmission
  • Light weight glazing sheet
  • UV resistant for durability
  • Durable and hardwearing
  • Minimum condensation risk
  • Largely self-cleaning
  • 10 year warranty

ideal for

  • Greenhouses
  • Sunscreens
  • Swimming Pool Covers
  • Vertical Panels
  • Plant Houses
  • DIY Glazing Projects


Refer to the Corotherm installation guide and installation video for complete installation instructions.

Energy Efficiency - Relative U-Values*

Sheet Thickness(mm) Corotherm Single Glass Double Glass Argon Filled Cavity
6mm (Twinwall)




10mm (Twinwall)




16mm (Triplewall) 2.4 5.4 2.65 1.6
25mm (7Xwall) 1.6 - 2.65 1.6

*A lower U-value indicates increased energy efficiency and thermal insulation 


  • Make sure the clearly marked UV protected side of the sheet is facing outwards
  • Allow a minimum of 10° roof slope for water drainage
  • Use only low modulus neutral cure sealant and cross-linked butyl flashing tape
  • The flutes of the sheets must run from top to bottom of the slope, never from side to side
  • Sheets cannot be joined top to bottom

Corotherm can be easily cut and will not crack or shatter.  When cutting parallel to the flutes a sharp knife can be used but when cutting across the flutes a fine toothed saw is required.  For cutting curves use a fine toothed jig saw.

Thermal Expansion
When installing Corotherm sheet it is important to allow a sufficient expansion gap at the top end of the sheet.  When drilling fixing holes an expansion allowance of 3mm around all fixings is required.  Do not fix or clamp sheets too tighly - leave room for thermal movement.

Corotherm can be easily and quickly washed with luke warm soapy water and a soft cloth or sponge.  Do not use brushes or sharp objects and avoid any abrasives or cleaners of high alkaline nature.

10 Year Warranty
This product is covered by a 10 year warranty. A replacement is provided free of charge if the product has failed due to a manufacturing defect, in normal climatic conditions within a 10 year period from the date of purchase.

Corotherm MUST be fixed and maintained in accordance with the manufacturer's instructions for the warranty to remain valid: re-erections or consequential damage costs are not included.


  • Sheet End Cap

    Sheet end cap for use with Corotherm sheet

    View product
  • Standard Fixing Buttons

    Fixing screws with covering button and seal for use with 6mm Corotherm sheet

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