Twin Wall to Twin Wall Increaser Ø 80 - Ø 100
At a Glance
- Premium dual stainless steel construction (304 outer, 316 inner)
- Bridges diameters from Ø80 to Ø100 in 25mm increments
- Suitable for wood stoves, gas, oil, and low sulphur coal appliances
- Compressed rockwool insulation (200kg/m³) for enhanced thermal efficiency
- HETAS approved and CE marked for reliable safety
- Easy installation with a secure Locking Band

Please Note: All dimensions refer to the internal diameter of flues. If unsure, please call 01670 206999 to ensure you choose the correct products.
We Won't Be Beaten On Price
At National Flues, we continuously monitor competitor prices. This ensures that we consistently offer you the best deals on all our products. Here’s how we keep your costs low:
- Daily Price Matching: Our team adjusts prices to ensure we stay competitive.
- Bulk Purchasing Power: We sell a lot, so we can negotiate better rates with suppliers, passing the savings directly to you.
- Operational Efficiency: We have streamlined processes to reduce overhead.
Price Match Guarantee: If you find the same product cheaper within 48 hours, we’ll match it and refund the difference.
Free Delivery Over £100: Orders over £100 are free delivery (call us if delivery is required outside the mainland UK).
“I saved 20% on my purchase compared to other retailers. Exceptional service!” – Jane D.
Have Questions?
Phone: 01670 206999
Email: [email protected]
- Info
- Specs
- Install
- FAQs
The Twin Wall to Twin Wall Increaser Ø 80 - Ø 100 is your ultimate solution for enhancing chimney performance for both solid fuel and gas/oil appliances. This high-quality increaser is perfect for wood stoves, gas coal effect fires, oil and gas boilers, and any other solid fuel appliances. Crafted with precision, the outer skin is made from 304 grade stainless steel at 0.4mm thickness, while the inner skin boasts 316 grade stainless steel, also at 0.4mm thickness.
To ensure outstanding insulation, we've used compressed rockwool with a density of 200kg/m3. All components are fully welded to guarantee durability and safety, maintaining a mandatory 50mm distance from combustibles. Approved by HETAS and CE marked, this increaser meets the highest safety standards (EN1856-1 T600 N1 W V2 L50040 G50; EN1856-1 T200 W V2 L50040 O20).
Installation is a breeze, secured effortlessly with a Locking Band. Enhance your flue system today with a product that doesn’t compromise on quality or safety.
SKU: 2-80-004
Technical Specifications | |
---|---|
SKU | 2-80-004 |
Dimensions | Diameters u00d880 to u00d8100, increasing in 25mm increments |
Outer Material | 304 Stainless Steel, 0.4mm thick |
Inner Material | 316 Stainless Steel, 0.4mm thick |
Insulation | Compressed Rockwool, 200kg/mu00b3 |
Fuel Compatibility | Wood, Oil, Gas, Low Sulphur Coal |
Approvals | HETAS, CE marked (EN1856-1 T600 N1 W V2 L50040 G50; EN1856-1 T200 W V2 L50040 O20) |
Installation Distance | Minimum 50mm from combustibles |
Fixing Method | Secured with a Locking Band |
Delivery Information +
We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Tuesday, April 8th. If you need faster stove or fireplace delivery please give us a call. We can often reduce longer lead times if we pay the carrier £25 for express delivery. Visit our Shipping Information page for more information.
Warranty & Returns +
All our products come with warranties. Mi-Flex offers a lifetime guarantee. Returns for damaged items are covered by insurance; non-damaged returns incur return delivery costs.
Price Match Guarantee +
We will match any price like for like. If you find it cheaper within 48 hours, we'll refund the difference.
Compatible and other products that may be of interest...
National Flues Ltd Verdict
At National Flues, we confidently recommend our Twin Wall to Twin Wall Increaser Ø 80 - Ø 100 for its impeccable build and versatile application. Enjoy reliable delivery and competitive prices whether you're a retail or trade customer.
This product is designed to seamlessly increase the diameter of flue pipes from Ø 80 to Ø 100, enhancing the efficiency and safety of your chimney system.
National Flues is a leading supplier of high-quality fireplaces and flues in the UK. Known for unbeatable prices and reliable delivery, we serve both retail and trade customers nationwide. Secure online payments available for a hassle-free shopping experience.
