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Insulation Back Filler - Ø 150

The Insulation Back Filler - Ø 150 is a high-quality accessory from National Flues, designed to streamline your chimney installation process. This MI-FLEX product not only complements flexible flue liners but also stands out as a reliable, durable solution for effective chimney back filling with ver... More...
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At a Glance

  • - Designed for effortless chimney back filling with vermiculite
  • - Compatible with MI-FLEX 316 and 904 flue liners
  • - Manufactured in premium 316L stainless steel for longevity
  • - Fully compliant with Building Regulations Document J
  • - Engineered for solid fuel, gas, oil and smokeless coal appliances
Now only £42.49
Including VAT Buy with confidence. If you find this cheaper within 48 hours of checkout, we'll refund the difference.

 

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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]

The Mi Flues Screw-FIX Insulation Back Filler - Ø 150 is a cutting-edge solution for efficiently back filling your chimney with vermiculite, designed specifically for use with Screw-Fix pot hanging cowls and MI-FLEX flue liners. This premium accessory is engineered to work seamlessly with both MI-FLEX 316 and 904 flexible flue liners, ensuring a cohesive and fully functional chimney system. Compliant with Building Regulations Document J, this product can be used with appliances up to 600°C (T600 designation) and is suitable for wood (less than 20% moisture), smokeless coal, gas, and oil.

Our Screw-Fix accessories are crafted to facilitate the installation and maintenance of multi-fuel flue liners, housed completely within masonry chimneys—a non-masonry enclosure like timber or plasterboard is not permissible. Regular chimney sweeping and maintenance are critical, especially for solid fuel appliances, and should be conducted by a certified professional. Avoid using chemical cleaners or mild steel tools on stainless steel chimneys.

We advise sweeping twice annually: at the end of the heating season and before the start of the next season.

SKU: 25-150-VBF

Technical Specifications
SKU25-150-VBF
Diameteru00d8 150
Material316L Stainless Steel
SystemMI-FLEX Accessories MF20
CertificationsCE / HETAS
Fuel CompatibilityWood (less than 20% moisture), Smokeless Coal, Gas, Oil
Temperature RatingUp to 600u00b0C (T600 designation)
Ensure that the Insulation Back Filler is installed within a masonry chimney only, as prescribed by Building Regulations. Always pair with Screw-Fix pot hanging cowls and MI-FLEX flue liners. During installation, confirm that vermiculite is evenly distributed to fully insulate the chimney lining. Regular maintenance is key—schedule chimney sweepings at the end of the heating season and before the next season begins. Use appropriate tools designed for stainless steel to avoid scratching; chemical cleaners or mild steel tools are not recommended. Finally, adhere strictly to manufacturer guidelines to ensure long-term reliability and safety.

It is a bespoke accessory designed to streamline the process of back filling your chimney with vermiculite when used in conjunction with a Screw-Fix pot hanging cowl and MI-FLEX flue liners.

The Insulation Back Filler is suitable for use with appliances that operate up to 600°C, including those using wood (with less than 20% moisture), smokeless coal, gas, and oil.

Yes, it meets the requirements of Building Regulations Document J, mandating that flexible flue liners must be enclosed entirely within masonry chimneys.

No, the product must be used within a masonry chimney. Non-masonry enclosures like timber or plasterboard are not acceptable.

Chimneys serving solid fuel appliances should be swept at least twice a year: once at the end of the heating season and again before the beginning of the next heating season.

Use appropriate tools for stainless steel chimneys; avoid chemical cleaners or mild steel tools. Sweeping should be performed by a competent professional.

For solid fuel applications, a list of HETAS registered sweeps can be found at www.hetas.co.uk.
Delivery Information +

We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Thursday, April 3rd. 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.

Read our buyers guide for this Insulation Back Filler - Ø 150

National Flues Ltd Verdict

At National Flues, we highly recommend the Mi Flues Screw-FIX Insulation Back Filler. This innovative product simplifies the process of back filling your chimney with vermiculite while ensuring compliance with Building Regulations. We are rarely beaten on price, offer reliable delivery, and cater to both retail and trade customers nationwide.

The Mi Flues Screw-FIX Insulation Back Filler is designed to simplify the back filling of chimneys with vermiculite, ensuring proper insulation and compliance with regulations when using flexible flue liners.

National Flues is a trusted supplier of fireplaces and flues in the UK, dedicated to providing high-quality products at competitive prices, with reliable delivery and excellent customer service for both retail and trade customers.

 

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Don’t compromise on safety – secure your chimney’s efficiency with the Mi Flues Screw-FIX Insulation Back Filler now.

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