Product Description

TWPro 125mm Twin Wall Insulated Anti-Wind Cowl – Matt Black

Model: 37-125-091

Protect the top of your chimney with the TWPro 125mm Twin Wall Insulated Anti-Wind Cowl. This terminal combines a central rain cap with an outer wind shield. As a result, it helps reduce direct rain entry and limits the effect of wind around the flue outlet.

The durable matt-black finish matches other black TWPro and compatible KW Flue components. Therefore, it provides a neat finish for an exposed twin-wall chimney system.

Key Features

• Designed for 125mm internal-diameter TWPro twin-wall flue
• Anti-wind outer cover surrounds a central rain cap
• Helps protect the chimney from wind and direct rainfall
• Suitable for compatible solid-fuel, gas and oil appliances
• Matt-black powder-coated finish
• Push-fit FitSystem joint with locking band
• Maximum operating temperature class: T600
• Declared distance to combustible materials: 50mm
• Product model: 37-125-091

Wind and Rain Protection

This anti-wind cowl provides more weather protection than a basic open terminal. First, the central cap helps limit direct rain entry. In addition, the outer cover shields the flue outlet from wind approaching from different directions.

However, no chimney cowl can correct every draught problem. Chimney height, nearby buildings, trees, roof shape and local wind conditions can all affect performance. Therefore, ask a competent installer to assess the complete chimney if you experience smoke blowback or poor draught.

Application

Use this terminal at the top of a compatible 125mm TWPro or KW Flue twin-wall insulated chimney. It suits compatible wood-burning stoves, multifuel stoves, gas appliances and oil-fired appliances, subject to the appliance and flue-system instructions.

The stated 125mm size refers to the internal flue diameter. Because TWPro includes 25mm of insulation around the inner flue, the main pipe has an external diameter of approximately 175mm.

This cowl only fits compatible TWPro and KW Flue components. Do not connect it to another flue brand unless the manufacturer confirms compatibility in writing.

TWPro 125mm Anti-Wind Cowl Specification

• Download the TWPro Matt Black information sheet
• View the TWPro installation guide
• Read why we recommend TWPro twin-wall flue
• Product type: anti-wind chimney terminal
• Nominal internal diameter: 125mm
• Approximate system outside diameter: 175mm
• Finish: matt black
• Inner casing: 0.4mm 316L-grade stainless steel
• Outer casing: 0.4mm 304-grade stainless steel
• Insulation: 25mm injected mineral wool
• Joint method: FitSystem push fit with locking band
• Maximum operating temperature class: T600
• Minimum declared distance to combustible materials: 50mm
• System warranty: 25 years, subject to terms and conditions
• Paint-finish warranty: 2 years, subject to terms and conditions

Approvals and Classification

• HETAS approved system
• CE marked: EN 1856-1 T600 N1 W V2 L50040 G50
• CE marked: EN 1856-1 T200 P1 W V2 L50040 O20

The G50 designation declares a 50mm minimum distance between the outer surface of the chimney and combustible materials under the stated test conditions. However, always follow the appliance instructions, system installation guide and Building Regulations. If another part of the installation requires a greater clearance, use the greater distance.

Installation Guidance

Fit the anti-wind cowl to the top of the final compatible TWPro chimney section. Then secure the joint with the correct locking band. Also check that the terminal remains vertical, stable and clear of nearby obstructions.

The chimney termination position must meet current Building Regulations and the appliance manufacturer’s instructions. Furthermore, the chimney must extend high enough to support safe flue-gas dispersal and reliable draught.

Do not use the cowl to support the chimney. Instead, use the correct wall supports, roof supports and structural components throughout the system. We recommend installation by a suitably competent professional, such as a HETAS-registered installer when appropriate.

Maintenance

Inspect the cowl regularly for soot, tar, bird debris and other blockages. In addition, check its condition after severe weather. Keep all outlet openings clear so flue gases can escape freely.

Arrange chimney sweeping at intervals that suit the appliance, fuel and frequency of use. During each service, ask the installer or chimney sweep to check the terminal, locking band and nearby chimney sections.

About the TWPro Twin-Wall Flue System

TWPro provides a complete insulated stainless-steel chimney system for domestic heating appliances. Its FitSystem design uses push-fit joints and locking bands, which helps make assembly quick and secure.

The smooth matt-black outer casing suits both modern and traditional properties. Meanwhile, the insulated construction keeps the inner flue warmer and helps maintain a stable chimney draught.

Why Buy from SNH Tradecentre?

• Specialist stove, chimney and flue-system supplier
• Extensive range of matching TWPro components
• Practical technical advice from an experienced team
• Nationwide UK delivery options
• Secure online ordering
• Trade counter in Birchington, Kent
• Support before and after your purchase

Need help choosing the correct terminal for your chimney? Call SNH Tradecentre on 01843 842727 before ordering.

Frequently Asked Questions

What does an anti-wind cowl do?

The outer cover shields the flue outlet from wind, while the central rain cap helps limit direct water entry. Therefore, this design provides added weather protection at the top of the chimney.

Will this cowl stop chimney downdraught?

It may reduce wind-related disturbance around the terminal. However, downdraught can also result from chimney height, nearby obstructions or an unsuitable flue design. Ask a competent installer to identify the cause before changing the terminal.

Does this cowl fit a 125mm stove pipe?

It fits the top of a compatible 125mm TWPro or KW Flue twin-wall chimney. It does not connect directly to ordinary 125mm single-wall stove pipe.

What is the outside diameter?

The 125mm measurement refers to the internal flue diameter. The matching twin-wall system has an approximate external diameter of 175mm.

Can I use it with another twin-wall flue brand?

No, unless the manufacturer provides written confirmation of compatibility. Twin-wall systems can use different joint profiles and locking methods, even when they share the same internal diameter.

Is it suitable for a wood-burning stove?

Yes, it suits compatible wood-burning and multifuel appliances. However, always confirm the required chimney specification in the appliance instructions.

How far must the system remain from combustible materials?

The system carries a G50 designation at T600, which declares a minimum distance of 50mm. Nevertheless, follow any greater clearance required by the appliance instructions, installation design or Building Regulations.

Does the cowl include a warranty?

The TWPro system carries a 25-year warranty, subject to its terms and conditions. The matt-black paint finish carries a separate two-year warranty, also subject to its conditions.