All Weather Cowl – Twin Wall Pipe 125mm (Black)

£86.67 Inc VAT

HETAS approved, black and Stainless Twin Wall flue components and associated parts for creating new internal and external flue systems.

Available in 125mm-200mm internal diameters, all insulated parts feature a 25mm layer of Rockwool insulation, creating a 50mm greater outer diameter and come supplied with a Locking Band where applicable.

Twin wall flue size guide

1. Pipe and elbow diameters

With twin wall flue pipe, the internal and external diameters are different. This is because they have 1 inch of insulation surrounding the inner pipe that makes the outer pipe 2 inches larger than the inner pipe. The diameters referred to always relate to the INTERNAL diameter of the pipes it is this diameter that is important when connecting your flue pipe to a stove.

2. Brackets and finishing plates

Due to the reasons above all brackets and plates that are cut to fit twin wall pipe will actually measure 2 inches more than their stated diameter.

Stated Diameter I = Internal Diamater E = External Diameter Brackets & plate Diameter
100mm (4″) 100mm 150mm 150mm
125mm (5″) 125mm 175mm 175mm
150mm (6″) 150mm 200mm 200mm
175mm (7″) 175mm 225mm 225mm
200mm (8″) 200mm 250mm 250mm

Other useful information regarding twin wall flue systems

  • Your flue system (internal diameter) must never be less than the flue collar diameter on your stove and the stated flue requirements of that stove.
  • You can increase but never decrease the diameter of your flue system.
  • For that reason we do not sell reducers or decreasing components.
  • You should have a maximum of 4 elbows in your system.
  • The maximum angle of a bend permitted is 45 degrees other than coming straight out the back of your stove.
  • You should aim for an overall height of at least 4.5 meters from the top of your stove for the flue to work well.
  • The outlet or terminal of your flue system needs to finish at least 1000mm above your roof or 2,300mm horizontally from your roof, or 600mm above the ridge of your roof, whichever comes first.
  • Need help planning your system? Call us on 01376 315 760 to speak to our HETAS approved team of specialists who can plan your building regulation compliant system with you.

All Weather Cowl – Twin Walled Pipe

Push-fit All Weather Cowl for ultimate protection against the elements for a twin wall flue system. Featuring extra protection around the terminal, this Cowl is ideally suited to flue systems in exposed areas or waterfronts or suffer from wind channelled across the flue.

Please note, this item is not advised for flue systems under 4m in length due to potential impact on the draw. Similarly, no terminal is designed to be 100% water-tight as this would impact the draw of the stove.

Also available in Open-Sided and Meshed versions.

Available in Stainless and black finishes, for 125mm-200mm internal diameters.

Please note – As with all twin wall parts the diameter quoted is the internal diameter – The external diameter is 2 inches larger due to the surrounding insulation.

Designation number T450-N1-D-Vm-L50050-G60

  • Finish: Black
  • Internal Diameter: 125mm
  • External Diameter: 175mm
  • Height: 350mm
  • Insulated: Yes
  • Locking Band Supplied:Yes
  • Warranty: 12yrs
  • Grade: 316

Additional information

Colour

Black

Flue Diameter

125mm

Flue Parts

Cowl/Terminal

Terminal Type

Rain cap, Bird guard, Anti downdraught

To Fit

Twin wall pipe