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MI-Flex Flexible Flue Liners - Durable and Flexible Flue Solution

MI-Flex is a top-tier choice for flexible flue liners, renowned for its durability and flexibility in chimney installations. The MI-Flex range includes options in various diameters to suit different chimney sizes. The high-quality stainless steel construction ensures longevity and resistance to heat and corrosion. Whether you're fitting a new stove or updating an existing fireplace, MI-Flex provides a reliable solution. Discover why MI-Flex is a preferred choice among installers and homeowners for safe and efficient chimney lining.

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StovesPremium Stoves
FireplacesStunning Fireplaces
MI-FlexFlexible Liner
Chimney FlueChimney Flue
Connecting PipesConnecting Pipes
Fans Flashings CowlsFans Flashings Cowls
Installation PartsInstallation Parts
After Care PartsAfter Care Parts

The best selling flue liner in the UK. Suitable for gas, oil, and approved solid fuels. Call our advisers on 01670 206 999 if you need any help choosing.

£37.99

25-175-MR

Screw-FIX Increaser - Ø 175-200mm

Screw-FIX Increaser - Ø 175-200mm

£66.99

25-175-MR1

Screw-FIX Increaser, 1mm - Ø 175-200mm

Screw-FIX Increaser, 1mm - Ø 175-200mm

£46.99

25-175-THA

Screw-FIX Top Hat Adaptor - Ø 175

Screw-FIX Top Hat Adaptor - Ø 175

OUT OF STOCK

£121.49

20-180-PHAD

Pot Hanger with AD Cowl (Natural) - Ø 180

Pot Hanger with AD Cowl (Natural) - Ø 180

£74.49

20-180-PHCMP

Premium PH Cowl (Natural) - Ø 180

Premium PH Cowl (Natural) - Ø 180

OUT OF STOCK

£79.99

20-180-PHCMTP

Premium PH Cowl (Terracotta) - Ø 180

Premium PH Cowl (Terracotta) - Ø 180

OUT OF STOCK

£34.99

20-180-PHS

Pot Hanger - Ø 180

Pot Hanger - Ø 180

£40.99

20-180-PSRC

Top Insert Sleeve with Rain Cap - Ø 180

Top Insert Sleeve with Rain Cap - Ø 180

£38.49

20-180-RC

Rain Cap - Ø 180

Rain Cap - Ø 180

£105.49

20-180-SPHCM

MI-FLEX Square Pot Hanging Cowl (Natural) - Ø 180

MI-FLEX Square Pot Hanging Cowl (Natural) - Ø 180

OUT OF STOCK

£132.49

20-180-SPHCMT

MI-FLEX Square Pot Hanging Cowl (Terracotta) - Ø 180

MI-FLEX Square Pot Hanging Cowl (Terracotta) - Ø 180

OUT OF STOCK

£37.49

25-175-PHS

Screw-FIX Pot Hanger - Ø 175

Screw-FIX Pot Hanger - Ø 175

OUT OF STOCK

£37.99

25-175-RC

Screw-FIX Rain Cap - Ø 175

Screw-FIX Rain Cap - Ø 175

£10.49

20-180-C

Top Clamp - Ø 180

Top Clamp - Ø 180

£10.99

20-180-P

Top Plate - Ø 180

Top Plate - Ø 180

Your MI-Flex Questions Answered

What sizes are available in the MI-Flex range? -

MI-Flex is available in various diameters, including 80mm, 100mm, 125mm, 150mm, 175mm, 200mm, 250mm, and 300mm, catering to a wide range of chimney sizes.

Is MI-Flex suitable for wood-burning stoves? +

Does MI-Flex require professional installation? +

Can MI-Flex be used with gas fires? +

Is MI-Flex suitable for listed buildings? +

What is the warranty period for MI-Flex products? +

Can MI-Flex be used for both residential and commercial applications? +

MI-Flex stands out as a premium option for flexible flue liners in the UK. Its innovative design allows for easy installation, offering flexibility to navigate bends and offsets in chimneys efficiently. Made from high-grade stainless steel, MI-Flex ensures durability and longevity, making it a cost-effective solution in the long run. The smooth inner surface of MI-Flex promotes optimal airflow and prevents the build-up of creosote and debris, enhancing the efficiency and safety of your fireplace or stove. When it comes to quality, durability, and performance, MI-Flex is the go-to choice for chimney lining projects.
Why Buy MI-Flex Products
MI-Flex flexible flue liners are ideal for both residential and commercial properties. They are suitable for use with wood-burning stoves, multi-fuel stoves, gas fires, and oil boilers. MI-Flex offers a versatile solution for various chimney types, including masonry and pre-fabricated chimneys. Whether you're renovating an old property or installing a new heating appliance, MI-Flex provides a reliable and efficient flue lining solution. Its flexibility and durability make it a popular choice among installers and homeowners looking for high-quality chimney components.

Trusted By Trade Professionals

Our MI-Flex products and services are trusted by hundreds of professionals nationwide. We're committed to providing quality and reliability that meets the high standards of our customers.

Dedicated Support

Experience our unparalleled customer service and support when you buy MI-Flex from National Flues. Our team is here to assist you every step of the way, ensuring your needs are met with expertise and care.

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