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Top Insulation for Fireplaces and Flues at Unbeatable Prices - UK

When it comes to keeping your fireplace and flues working efficiently, insulation plays a crucial role. Our MI-Flex insulation, including the durable 904L Mi-FLEX and 100MM (4 INCH) options, ensures optimal heat retention and safe operation. Whether you're looking to upgrade existing insulation or start fresh, our products provide unmatched quality and performance.

Shop By Department

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.

£26.99

90-LECA

Leca 50L Bag

Leca 50L Bag

£26.49

90-RPS-T

Aluminium Tape

Aluminium Tape

£33.99

90-VERM

Vermiculite (100L Bag)

Vermiculite (100L Bag)

Your Insulation Questions Answered

What are the advantages of using MI-Flex insulation? -

MI-Flex insulation offers superior heat retention, durability, and safety for your fireplace and flues. It helps improve efficiency and protect surrounding structures from heat damage.

Is MI-Flex insulation easy to install? +

Can MI-Flex insulation withstand high temperatures? +

Do I need insulation for my fireplace if it's already built? +

Are MI-Flex insulation products environmentally friendly? +

Can MI-Flex insulation help reduce heating costs? +

How long does MI-Flex insulation last? +

Proper insulation is essential for maintaining the efficiency and safety of your fireplace and flues. Our MI-Flex insulation range offers top-of-the-line solutions designed to withstand high temperatures and harsh conditions. With easy installation and long-lasting durability, our 904L Mi-FLEX and 100MM (4 INCH) options are ideal for both domestic and commercial applications. Invest in quality insulation today to enhance the performance of your fireplace and flues and create a cosy environment for your family and guests.
Why Buy Insulation Products
Our MI-Flex insulation products are perfect for various applications, including lining flue systems, insulating chimneys, and improving overall heat retention in fireplaces. The robust construction and heat-resistant properties make them suitable for use in a wide range of settings, from traditional homes to modern buildings. Upgrade your insulation today to enjoy increased efficiency, reduced heat loss, and enhanced safety in your fireplace and flues.

Trusted By Trade Professionals

Our Insulation 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 Insulation 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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