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Top Plate - Ø 125 (20-125-P)

Enhance your chimney system with the Top Plate - Ø 125 from National Flues, a premium accessory for MI-FLEX flexible flue liners. This high-quality component, with its robust GALV construction and natural stainless steel finish, is essential for maintaining the safety and efficiency of your fireplace or flue system. Read more...
Top Plate - Ø 125
IN STOCK
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Now only £11.99
Give us a call if you find it cheaper and we'll normally price match.
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At a Glance

  • Robust construction engineered for MI-FLEX 316 and 904 flexible flue liners
  • 400mm square design for optimal weight distribution
  • Suitable for multiple fuel types including wood, oil, gas, and smokeless coal
  • Compliant with Building Regulations Document J and approved by HETAS/CE
  • Engineered for high temperature performance (up to 600°C T600 designation)
  • Made from durable GALV material with a Natural / Stainless Steel finish

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: sales@nationalflues.com

The Top Plate - Ø 125 is a critical component designed to provide strong support for MI-FLEX 316 and 904 flexible flue liners. Measuring 400mm square, this plate works in sync with a Top Clamp and Top Insert Sleeve, ensuring that the flue liner’s weight is effectively managed at the top of your chimney stack. Manufactured to comply with Building Regulations Document J, this top fixing accessory is suitable for a range of fuel types including wood (with moisture content <20%), smokeless coal, gas, and oil.

Rated for appliance use up to 600°C (T600 designation), our top plate guarantees a secure installation when adhered to correct guidelines. Proper chimney preparation is crucial – ensure that your chimney stack is fully weatherproofed, structurally sound, and that all pots are in good condition. For maintenance, an accessible design allows for easy inspection and cleaning, ideally performed twice a year by a certified professional, such as those registered with HETAS.

Cleaning should never involve chemical agents or mild steel tools to avoid damage to stainless steel parts. This top plate is not just a purchase; it’s a long-term investment in the safety and efficiency of your chimney system.

SKU: 20-125-P

Delivery Information* +

We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Friday, November 14th. This is based on current lead times. Bear in mind that it is a busy time of year. If you need a product delivered by a specific time in the next 7 days, then please give us a call on 01670 206 999. Visit our Shipping Information page for more information.

About National Flues Ltd +

We began over 30 years ago as a fireplace shop in the North East. We now supply hundreds of trade professionals and thousands of retail customers, all across the UK, every month. We are still a family owned business, lead by the MD Neil, and always try our best to deliver the best possible experience. We also price match, so give us a call if you find this cheaper and want to buy from us. Visit our about us page to read a bit more.

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Technical Specifications
Size400mm square
MaterialGALV (Galvanised)
FinishNatural / Stainless Steel
Compatible WithMI-FLEX 316 & 904 flexible flue liners
Fuel TypesWood (<20% moisture), oil, gas, smokeless coal
Temperature RatingUp to 600°C (T600 designation)
CertificationsHETAS, CE
System DesignTop Plate works in tandem with Top Clamp and Top Insert Sleeve
Before installing the Top Plate - Ø 125, ensure that your chimney stack is fully weatherproofed and structurally sound. Begin by confirming all chimney pots are in optimal condition. The following steps should be adhered to for a secure installation: 1. Verify that the chimney lining is correctly positioned and that the flue liner fits seamlessly with the Top Plate, Top Clamp, and Top Insert Sleeve system. 2. Position the Top Plate at the top of the chimney stack, ensuring it is level and secure. 3. Follow all manufacturer guidelines and local Building Regulations to guarantee compliance and safety. 4. Schedule annual or biannual inspections by a certified professional (preferably a HETAS registered chimney sweep) to maintain safe operation. Warning: Do not use chemical cleaners or mild steel tools on the stainless steel components, as this may cause irreparable damage. Ensuring precise installation and regular maintenance will maximise the lifespan and effectiveness of your chimney system.

The Top Plate - Ø 125 measures 400mm square, making it suitable for supporting flexible flue liners at the top of a chimney stack.

The Top Plate is designed for use with MI-FLEX 316 and 904 flexible flue liners and is suitable for wood, smokeless coal, gas, and oil appliances.

Ensure that your chimney stack is fully weatherproofed, structurally sound, and that all chimney pots are in good condition before installation.

The Top Plate is rated for use with appliances up to a maximum temperature of 600°C (T600 designation).

Your chimney should be cleaned and inspected at least once a year, or ideally twice if used for solid fuels, by a certified professional.

No, chemical cleaners and mild steel tools should not be used on stainless steel chimneys to avoid damage.

For solid fuel appliances, a list of HETAS registered sweeps is available at www.hetas.co.uk.

 

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