Kayflow rainwater systems are suitable for all applications and types of building, including domestic, commercial and industrial.

Rainwater gutters and downpipes are manufactured in the UK by a continuous extrusion process. Fittings are produced on high-pressure injection moulding machines. All fittings are manufactured to close tolerances to allow accurate incorporation of design features.

All products in the rage are manufactured from unplasticised polyvinyl-chloride (PVC-U) and comply with the material requirements of either BS EN 12200-1:2000, BS EN 607:2004, or BS EN 1462:2004 as relevant.

picture of black guttering attached to a white fascia board on a roof

Features and Benefits of Kayflow Guttering and Downpipes

  • Suitable for all types of buildings including domestic, commercial and industrial.
  • Practical rainwater handling systems which, unlike metal systems, do not conduct lightning.
  • Components have a consistent self-finish and colour, and are essentially maintenance free.
  • Tough and durable, yet lightweight for ease of installation, they will withstand normal ladder weight.
  • High gloss finish with blemish free surface providing excellent all round weathering and colour fastness.
  • Comprehensive range of systems, colours and fittings to provide solutions to all installation requirements.
  • Cost effective solution to rainwater collection and drainage.
  • Well defined stylish contours ensure a seamless match with the architecture of all properties, new or old.
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What size system do I need?

To select the gutter size appropriate to your requirements, two factors must be taken into consideration:

  • Roof area
  • Gutter flow capacity

For further reference refer to BS 12056-3:2000 ‘Roof Drainage Layout and Calculation‘.

The capacity of the drainage system should be large enough to carry the expected flow at any point int he system. The flow of ‘run-off’ depends upon the area to be drained, (the ‘effective roof area’), and the intensity of rainfall. It is acceptable that 75mm an hour is the intensity of rainfall in the UK.

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Rainwater System Compatibility Chart

Manufacturer Xtraflo 170mm Niagara Ogee Hi-Cap Half-Round 112m Square Line MiniFlo
(No equivalent)


(High capacity)



Brett Martin
(No equivalent)





(No equivalent)
(No equivalent)





(No equivalent)



(Half round)
Polypipe Terrain
(No equivalent)





(No equivalent)
(No equivalent)





(No equivalent)




(Half Round)
Marshall Tufflex

(Universal Plus)

(Universal XL)

(No equivalent)

Watch Our Installation Guide

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