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125mm (5 inch) Sheffield Pattern Flue Box (8-SHEF)

National Flues introduces the 125mm (5 inch) Sheffield Pattern Flue Box—a superior, twin-wall flue box that redefines easy installation for gas fireplaces. Engineered for installations within existing builders' openings, this product is not only compliant with BS5258 (Part 5) standards but is also ideal for appliances such as the Valor Firelite Oxysafe. Whether you refer to it as a flue box, chimney flue accessory, or gas fire channel, this product guarantees a seamless, durable, and safe installation solution.
£141.99
with free delivery Give us a call if you find it cheaper and we'll try to price match.

 

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At a Glance

    Twin-wall durability ensuring long-lasting performance
    Reduced height and increased depth for hassle‐free installation
    Fully compliant with BS5258 (Part 5) safety standards
    Designed for easy fitting in existing builders'' openings
    Ideal for gas fires including the Valor Firelite Oxysafe

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 125mm (5 inch) Sheffield Pattern Flue Box is expertly crafted for a hassle-free fitting experience. Its twin-wall design ensures superior durability and safety, making it a reliable choice for installations in existing builders' openings. The cleverly reduced height and increased depth of the box mean you can skip extensive post-installation construction work, saving both time and effort.

This flue box is compliant with BS5258 (Part 5) standards, making it suitable for a range of gas fires, including the Valor Firelite Oxysafe. Whether you're a trade professional or a DIY enthusiast, this flue box makes a splendid addition to your toolkit.

SKU: 8-SHEF

Technical Specifications
Size125mm (5 inch)
DesignTwin-wall construction
ComplianceBS5258 (Part 5)
Suitable ForValor Firelite Oxysafe and similar gas fires
InstallationSpecifically engineered for existing builders' openings
MaterialHigh grade, heat-resistant components
FinishStandard finish as shown in product images
DeliveryNationwide availability in the UK
Begin by ensuring that the existing builder's opening is clear of obstructions and debris. Measure the opening carefully to confirm that the reduced height and increased depth of the Sheffield Pattern Flue Box will fit securely. Follow these key steps: 1. Prepare the site: Clean the builder's opening and check for any irregularities. 2. Position the flue box: Ensure it is level and centred in the opening to facilitate optimum performance. 3. Secure the unit: Use recommended fixings or adhesives to fasten the flue box in place, ensuring a stable installation. 4. Connect necessary components: Follow the installation manual carefully for attaching flue ducts or additional accessories. Important: Always adhere to local building regulations and safety standards. If in doubt, consult a certified professional for installation. Regular inspection post-installation is advised to ensure ongoing compliance and performance.

The Sheffield Pattern Flue Box is available in a 125mm (5 inch) size.

The flue box is suitable for fires compliant with BS5258 (Part 5), including the Valor Firelite Oxysafe.

The twin-wall design improves durability and ensures the flue system operates safely and efficiently.

No, the reduced height and extra depth of the box minimize the need for additional builders work after installation, saving time and effort.

Yes, the design is created to allow for quick and hassle-free installation into existing builders' openings.

Yes, National Flues provides reliable nationwide delivery for both retail and trade customers.

Yes, trade accounts are available for professional customers looking for regular purchases at competitive prices.
Delivery Information +

We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Tuesday, May 20th. Delivery times of products not in our warehouses depend on product availability and shipping. If you need a definitive delivery time give us a call. If you need faster stove or fireplace delivery please also give us a call. We can sometimes 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 on a retail basis. Give us a call if you find it cheaper and want to buy from us.

Read our review in our 125mm (5 inch) Sheffield Pattern Flue Box buyers guide

Upgrade your installation with a flue box that combines ease, compliance, and durability—order now for fast delivery!

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