Multiwall Polycarbonate


Multiwall polycarbonate glazing sheet is a high quality product produced in ‘clean-room’ conditions which helps to ensure that it retains its quality.

It is an ideal roof glazing material that offers remarkable impact resistance and long-term weather durability. It is virtually unbreakable and will withstand storms, hail-stones, wind, snowfalls and ice formation – as well as prolonged hot sunny weather. It performs extremely well in temperatures as low as -40 degrees C and as high as +120 degrees C.

In addition, it has high levels of light transmission and superb heat insulation characteristics, both of which offer cost savings by conserving energy – important when we are all trying to cut down on carbon emissions. Multiwall polycarbonate is also very light in weight compared with glass, making it much easier to lift on to a roof. Because it is so tough there will be no breakages during installation, and being light in weight means that it doesn’t need heavy structures to hold it in place.

As well as the standard clear product, multiwall polycarbonate can also be supplied in opal or bronze tints, and a Venetian pattern (a thin white stripe). These tints/patterns are for use where levels of light transmission and/or solar heat gain need to be restricted, such as applications on a south or west facing roof.

The product features a proprietary UV coating that is designed to protect the sheet against the degrading effects of ultra-violet radiation in natural sunlight. UV will not be transmitted through this glazing, making it an ideal choice for playground canopies used to protect children from these harmful rays.

Typical applications where multiwall glazing is used include:

  • Industrial and commercial rooflights
  • School playground canopies and covered areas
  • Stadia roofing
  • Railway station and platform canopy roofing
  • Commercial greenhouses
  • Swimming pool roof covers
  • Partition walls
  • High level vertical glazing
  • Smoking shelter roofing
  • Greenhouses

It is also widely used in the domestic market for:

  • Conservatory roofing
  • Car ports
  • Patio covers
  • Sun room roofing
  • Cloches
  • Home greenhouses (where its unbreakability provides safety to young, playing children)

Impact Resistance

Despite its light weight, multiwall polycarbonate is much tougher and stronger than glass. It is virtually unbreakable and can withstand heavy storms, hailstones and snow.


At Twinfix we supply multiwall polycarbonate that has a UV coating. This protects if from the degrading effects of ultra-violet radiation in natural sunlight. Whilst our 16mm and 25mm sheet are coextruded with a UV-protective layer to both sides other thicknesses have only one side with this protection. This UV-protected side must face upwards/outwards when installed.


Care must be taken when handling and installing multiwall polycarbonate sheet in order to prevent damage. Each sheet is protected on both sides with a masking film. The film should remain on until installation. You should never use a craft knife to remove the film, as this will damage the surface. Simply peel the masking film away from edge where it will be covered by the glazing bars and remove it completely once installation is complete. Do not leave it in place once installation is finished. Sheet should be cleaned with warm soapy water, never use abrasive detergents or proprietary cleaning products.


Multiwall sheet is designed to be installed with the flutes going down the slope of the glazing, i.e. from ridge down to eaves, and not across.

Similarly when cold-bending multiwall sheet the flutes must be parallel to the bend or the sheet could be at risk of buckling.[/vc_column_text][/vc_column][/vc_row][vc_row][vc_column width=”1/1″][vc_cta_button call_text=”Purchase cut to size polycarbonate direct from Conservatory Roof Parts” title=”Get Price Now” target=”_self” color=”wpb_button” icon=”none” size=”btn-large” position=”cta_align_right” href=””][/vc_column][/vc_row]