TWPro is One of the Best Twin Wall Flues
TWPro Twin Wall Flue – Why It’s One of the Best Twin Wall Chimney Systems for Wood Burning Stoves
If you are installing a wood burning stove, log burner or multi-fuel stove and don’t have a suitable existing chimney, a twin wall flue system can provide the complete insulated chimney your stove needs.
But not all twin wall chimney systems are the same.
At SNH Tradecentre, our preferred choice is TWPro Twin Wall Flue – and there are some very good reasons why.
TWPro combines a 316-grade stainless steel inner liner, high-density insulation, T600 temperature rating, 50mm distance to combustibles, HETAS approval and a comprehensive range of components to create a high-quality chimney system suitable for professional stove installations.
If you’re comparing different brands of twin wall flue for a wood burning stove, don’t simply compare the price of a one-metre pipe.
Look at what you’re actually getting.
What Is Twin Wall Flue?
Twin wall flue – also known as twin wall insulated flue, double wall flue or insulated chimney pipe – is a factory-made chimney system consisting of an inner flue pipe, insulation and an outer protective casing.
Unlike ordinary single-wall stove pipe, twin wall flue is designed to retain heat within the chimney.
This makes it possible to create a chimney system where there isn’t a suitable conventional masonry chimney.
A typical installation may run:
- Internally through the property
- Through ceilings and floors
- Through a roof
- Through an external wall and vertically up the outside of the building
The exact installation depends on the stove, property and manufacturer’s installation requirements.
Why Choose TWPro Twin Wall Flue?
There are plenty of twin wall chimney systems available, so why are we such big fans of TWPro?
Because when you look beyond the shiny outer pipe, the specification is extremely impressive.
1. TWPro Is Rated Up to T600
This is one of the first specifications we’d look at when comparing chimney systems for solid-fuel appliances.
TWPro carries the designation:
EN1856-1 T600 N1 W V2 L50040 G50
The T600 part is particularly important.
It means the chimney system is designed for operating temperatures up to 600°C under its specified classification.
For a product being used with wood burning and solid-fuel appliances, that’s a serious specification.
When comparing twin wall flue systems, don’t just compare the price.
Compare the temperature classification.
2. 316 Grade Stainless Steel Inner Liner
The inside of a chimney has a tough job.
It’s exposed to hot flue gases, condensation and combustion products every time your stove is used.
TWPro uses a 316-grade stainless steel inner skin combined with a 304-grade stainless steel outer skin.
That’s exactly the sort of construction we want to see from a premium twin wall chimney system.
The inner and outer skins are both stated as 0.4mm thick, with fully welded construction.
It’s one of the reasons we believe TWPro represents such excellent value for money.
3. High-Density 200kg/m³ Insulation
Here’s something buyers often overlook.
What’s actually between the two walls of your twin wall chimney?
TWPro uses compressed insulation with a stated density of approximately:
200kg/m³
Why does insulation matter?
A chimney needs to maintain sufficient flue gas temperature to encourage a stable upward draught.
Good insulation helps retain heat within the flue rather than allowing it to escape unnecessarily through the outer wall.
This is particularly important on external chimney installations where the flue is exposed to colder outdoor temperatures.
So when you’re comparing one piece of twin wall pipe with another, don’t only look at how similar they appear externally.
Look at what’s inside them.
That’s where TWPro really starts to stand out.
TWPro vs Other Twin Wall Flue Systems
We don’t believe buying a chimney system should simply come down to finding the cheapest metre length online.
A twin wall chimney is an important part of your stove installation.
When comparing TWPro against alternative systems, we recommend looking at:
| Feature | What TWPro Offers |
|---|---|
| Inner liner | 316 grade stainless steel |
| Outer casing | 304 grade stainless steel |
| Inner thickness | 0.4mm |
| Outer thickness | 0.4mm |
| Insulation | High-density compressed insulation |
| Insulation density | Approx. 200kg/m³ |
| Temperature classification | T600 |
| Distance to combustibles | G50 / 50mm under stated designation |
| HETAS | Approved/listed for solid fuel applications |
| UKCA | Marked |
| Warranty | 25-year conditional product warranty |
| Fuel suitability | Wood, solid fuel, gas and oil applications subject to specification |
That’s why we think TWPro deserves serious consideration before choosing a cheaper alternative.
The cheapest twin wall flue isn’t necessarily the best-value chimney system.
Only 50mm Distance to Combustible Materials
One of TWPro’s standout specifications is its G50 designation.
Under its T600 solid-fuel designation, TWPro requires a stated 50mm distance from the outside of the chimney to combustible material.
This can be extremely useful when planning a chimney route through a property where space is limited.
Clearances must always be maintained correctly, and the complete installation must follow the manufacturer’s instructions and applicable Building Regulations.
Never reduce the manufacturer’s required clearance simply because a chimney is insulated.
HETAS Approved Twin Wall Flue
For anyone searching for a HETAS approved twin wall flue, TWPro should be firmly on the shortlist.
TWPro is stated as HETAS Approved and carries the relevant product certification for its intended applications.
That gives installers and homeowners confidence that they’re choosing a properly tested chimney system rather than buying components based purely on price or appearance.
TWPro Twin Wall Flue for Wood Burning Stoves
TWPro is an excellent option for creating a chimney for a wood burning stove or log burner, particularly where the property doesn’t already have a suitable chimney.
A common installation could begin with vitreous enamel single-wall stove pipe directly above the appliance before transitioning to TWPro insulated chimney using the appropriate adaptor.
From there, the TWPro chimney can continue through the building or externally, depending on the installation design.
This makes it possible to create a complete stove chimney system using compatible components designed to work together.
5 Inch Twin Wall Flue – 125mm TWPro
For appliances that permit a 125mm / 5-inch chimney, TWPro is available as a complete 5 inch twin wall flue system.
Components can include:
- 125mm straight twin wall flue lengths
- 125mm adjustable lengths
- 125mm elbows
- Single-wall to twin-wall adaptors
- Wall supports
- Wall brackets
- Firestop components
- Roof flashing components
- Storm collars
- Support components
- Terminals and cowls
Always check the stove manufacturer’s instructions and relevant regulations before selecting the chimney diameter.
6 Inch Twin Wall Flue – 150mm TWPro
TWPro is also available as a 150mm / 6-inch twin wall chimney system.
Six-inch twin wall flue is widely used for wood burning and multi-fuel stove installations and provides the same benefits of an insulated modular chimney system.
Whether you’re looking for 5 inch twin wall flue or 6 inch twin wall flue, using one complete compatible system is important.
Black TWPro Twin Wall Flue
Not every chimney needs to look industrial.
For installations where the chimney remains visible, black TWPro twin wall flue provides a much more discreet finish.
This can look particularly good with a black wood burning stove.
Instead of having black stove pipe suddenly changing to bright stainless steel, a black twin wall system can create a much cleaner visual transition.
It’s ideal for:
- Contemporary stove installations
- Traditional fireplaces
- Exposed internal chimney systems
- External chimney installations
- Cabins and garden rooms
- Extensions
- Properties without existing chimneys
For many installations, we’d choose black TWPro purely because the finished chimney can look superb.
Stainless Steel TWPro Twin Wall Flue
Prefer the traditional chimney appearance?
TWPro is also available in stainless steel.
Stainless TWPro is particularly well suited to external chimney installations where the chimney runs vertically up the outside of the property.
The choice between black and stainless twin wall flue is therefore largely determined by the desired appearance and installation.
TWPro’s Locking System Makes Installation Straightforward
A good chimney system isn’t only about the straight pipe.
It’s about how all the components work together.
TWPro sections connect using dedicated locking bands, creating a modular chimney system with compatible pipes, elbows, adaptors, supports and terminals.
Some newer TWPro components also feature the TWPro FitSystem, designed to make assembly quick and straightforward.
A well-designed component range matters enormously when you’re trying to build a complete chimney rather than simply buying a length of pipe.
Don’t Mix Different Brands of Twin Wall Flue
This is extremely important.
Twin wall chimney systems should not be treated as universally interchangeable.
A 150mm component from one manufacturer isn’t automatically compatible with a 150mm component from another.
Jointing systems, outer diameters, locking arrangements, insulation and product approvals can differ.
Once you’ve chosen TWPro, the chimney should be designed using the appropriate compatible TWPro components.
Don’t build a chimney from random pieces simply because they’re all advertised as “6 inch twin wall”.
Twin Wall Flue vs Single Wall Stove Pipe
Another common question is:
Can I use single-wall stove pipe instead of twin wall?
They perform different jobs.
Single-wall vitreous enamel stove pipe is generally used as the connecting flue pipe between the stove and chimney system where permitted.
Twin wall insulated flue is a chimney system.
You therefore shouldn’t assume that ordinary black stove pipe can simply continue through ceilings, roofs or combustible construction.
A correctly designed installation may transition from single-wall stove pipe to TWPro using the manufacturer’s appropriate single-wall to twin-wall adaptor.
Why Keeping the Flue Hot Matters
A chimney isn’t simply a pipe for smoke.
It needs to create and maintain adequate draught.
Hot combustion gases naturally rise through the chimney. As those gases rise, maintaining temperature helps the chimney operate effectively.
That’s one of the major reasons for using an insulated twin wall chimney system.
The insulation reduces heat loss through the chimney wall, particularly where the flue passes through colder areas or runs externally.
This is another reason why we’d pay close attention to insulation specification when comparing twin wall systems.
Is Cheap Twin Wall Flue Worth Buying?
There are some things we’d happily buy based primarily on price.
A chimney system isn’t one of them.
If two pipes look almost identical online but one is cheaper, ask why.
Compare:
- Stainless steel grades
- Material thickness
- Insulation
- Insulation density
- Temperature classification
- Distance to combustibles
- Product certification
- Component availability
- Warranty
- Manufacturer support
A twin wall chimney could potentially remain part of your home for decades.
Saving a relatively small amount by buying an unknown system may not represent particularly good value over the lifetime of the installation.
That’s why TWPro offers such a compelling balance between specification, quality and price.
TWPro Comes With a 25-Year Conditional Warranty
Another major advantage is the manufacturer’s 25-year conditional product warranty.
That’s a substantial warranty for a chimney system and another reason TWPro stands out when comparing competing products.
As always, warranty conditions apply, and the chimney must be correctly selected, installed, used and maintained in accordance with the manufacturer’s requirements.
So, Is TWPro Twin Wall Flue Any Good?
Yes – we think it’s an excellent twin wall chimney system.
At SNH Tradecentre, we particularly like the combination of:
T600 temperature classification
316 stainless steel inner liner
304 stainless outer casing
High-density 200kg/m³ insulation
50mm distance to combustibles under its G50 designation
HETAS approval
UKCA marking
25-year conditional warranty
Black and stainless finishes
5 inch and 6 inch options
Large range of compatible components
Put all of that together and TWPro becomes extremely difficult to ignore when you’re comparing twin wall flue systems for a wood burning stove.
It isn’t simply about buying a length of chimney pipe.
You’re buying a complete chimney system.
And that’s exactly why TWPro is our preferred twin wall flue range at SNH Tradecentre.
Frequently Asked Questions About TWPro Twin Wall Flue
What is TWPro twin wall flue?
TWPro is an insulated stainless steel chimney system suitable for applications including wood burning and solid-fuel appliances. It consists of stainless steel inner and outer walls separated by high-density insulation.
Is TWPro suitable for wood burning stoves?
Yes. TWPro is designed for solid-fuel applications including wood burning stoves and carries a T600 classification under its stated EN1856-1 designation.
Is TWPro HETAS approved?
Yes. TWPro is stated as HETAS Approved for solid-fuel applications.
What is TWPro made from?
TWPro uses a 316-grade stainless steel inner liner and 304-grade stainless steel outer casing, with both skins stated as 0.4mm thick.
What insulation does TWPro use?
TWPro uses compressed insulation with a stated density of approximately 200kg/m³.
What is the distance to combustibles for TWPro?
Under its T600 N1 W V2 L50040 G50 designation, the stated distance to combustible materials is 50mm. Installation instructions and applicable regulations must always be followed.
Can TWPro be used outside?
Yes. Twin wall insulated chimney systems are commonly used to create external chimney routes. The installation must use the appropriate supports, brackets, terminals and other components required for the particular installation.
Can I get black TWPro twin wall flue?
Yes. TWPro is available in a black finish, making it particularly attractive for visible stove and chimney installations.
Is TWPro available in 5 inch and 6 inch?
Yes. Popular sizes include 125mm (5 inch) and 150mm (6 inch). The correct diameter depends on the appliance and installation requirements.
Can I connect stove pipe to TWPro?
Yes, where the installation design permits it, the appropriate TWPro single-wall to twin-wall adaptor can be used to transition from compatible stove pipe to the insulated chimney system.
Can I mix TWPro with another twin wall brand?
You should not assume components from different chimney systems are compatible. Use the manufacturer’s approved compatible components throughout the TWPro chimney system.
How long is the TWPro warranty?
TWPro is supplied with a 25-year conditional manufacturer’s product warranty, subject to the manufacturer’s terms and correct installation, use and maintenance.
Buy TWPro Twin Wall Flue from SNH Tradecentre
If you’re planning a new wood burning stove installation, TWPro Twin Wall Flue is a system we’d strongly recommend considering.
Whether you need 5 inch twin wall flue, 6 inch twin wall flue, black twin wall flue, stainless steel chimney pipe, elbows, adaptors, wall brackets, roof components or terminals, the TWPro range allows you to build a professional insulated chimney system around your installation.
At SNH Tradecentre, we believe TWPro offers an outstanding combination of specification, build quality, component choice and value for money.
Building a new chimney for your stove?
Choose TWPro Twin Wall Flue – a serious chimney system for a serious stove installation.
Important: Chimney design and installation must comply with the appliance manufacturer’s instructions, the TWPro installation instructions and applicable UK Building Regulations. Solid-fuel installations should be carried out/certified through the appropriate competent-person or Building Control route.