Four Seasons Living
Flexiroof Design
  • What is Flexiroof made from?

    We use high tensile aluminium (70% stronger than normal aluminium), premium 3mm polycarbonate sheet, and stainless steel fasteners.

  • Is polycarbonate sheet available in clear?

    No, clear is too hot! We offer a medium grey sheet, cutting out:

    • ~100% of UV radiation
    • ~50% of visible light
    • ~20% of heat

    This is the best Goldilocks solution. Not too dark, not too light!

    We only use polycarbonate sheet because it is 15x stronger than the cheaper acrylic or perspex alternative many other companies use.

  • How does Flexiroof handle snow? High-wind? Salt-water?

    Flexiroof shelters not only look great, but they are also designed to last for decades, even in New Zealand’s wildest weather situations.


    Under snow load, some sag will occur, but as the melt occurs, our strong and elastic materials will return to their original forms.

    Normal window aluminium has an ultimate tensile strength (UTS) of 150 MPa. Our rafters have internal bracing ribs are made from higher tensile 6016 T6 aluminium (UTS 235 MPa.) and all our other extrusions are made from the even stronger 6106 T6 aluminium (UTS 260 MPa.)


    To ensure Flexiroof handles high-wind we:

    • Use 3.00mm sheet and trap it with geometry video so there are no holes in the sheet (corrugated polycarbonate is only 0.9mm thick)
    • Use polycarbonate sheet – 15x stronger than common acrylic or perspex alternatives
    • Use 10mm stainless fasteners

    In exposed places, during storms there may be sheet noise (in keeping with noises from the rest of the house!)

    We had several shelters hit by the Auckland West tornado in early 2018 and they all survived well.


    Flexiroof uses:

    • 6061 T6 aluminium and polycarbonate sheet which are inherently very corrosion resistant
    • Stainless steel fasteners – all steel will corrode over long periods of time when exposed to sea air

    A note regarding galvanic corrosion: “battery corrosion effect” can occur with dissimilar metals (such as stainless and aluminium) but for it to occur it needs moisture, salt, and a lot of time. If you are putting aluminium windows (or a Flexiroof shelter) on a fishing trawler you will definitely have a problem. Otherwise, here at Flexiroof we are certain we are using the best system possible.

Delivery & Installation
Flexiroof Owners