Glass Fibre Seals

Pyroglass Glass Fibre Seals


Unlike the majority of companies who provide a range of high temperature materials, we manufacture our own, round section knitted, glass fibre seals, which are available in white or grey/black.

Our glass fibre seals are suitable for operation in temperatures of up to 600°C. Compression/density can be varied to suit the high temperature application.

Our glass fibre products can be used in many applications such as:

  • Wood burning
  • Multi-fuel
  • Pellet stoves
  • Gas fires
  • Boiler casings
  • Heat exchanges
  • Flue systems
  • Ash pans
  • Burner mounting assemblies
Contact our engineers to find out more

We manufacture glass fibers with a bonding agent to trap many small air cells which makes them good thermal insulators. Glass fibre seals are supplied on reels, or fabricated to make ‘O’ rings, and cut lengths.


Product Gallery

  • What temperature will glass fibre seals operate at?

    Depending upon the application glass fibre seals are capable of withstanding 600°C

  • Do you have any products which operate at temperatures > 600°?

    Yes, we do have certain special materials - please contact our Sales Dept. to discuss.

  • What is your order processing time?

    It depends upon the product(s) and quantity needed. We are a manufacturer so there is usually a production lead time. 

    For most orders we can turn them around within 10-12 working days but it is always a good idea to check with us first. Lead times can also vary according to the time of year.  In the heating season we do get very busy.


  • What temperature will the adhesive backing on glass fibre seals/tapes withstand?

    The adhesive backing is purely a 'fixing aid' during assembly. The adhesive backing will degrade at temperatures of 180°C or above but has served its purpose once the glass fibre seal/tape is held in place by some other mechanical means.     


  • What is the best way to start to remove the amber release film at the beginning of the roll of adhesive backed product?

    Sometimes it can be a little fiddly to start but there is a technique and if you contact our Sales Dept. we can provide a detailed instruction.      


  • What is the difference between a 'woven' and a 'knitted' tape?

    Woven tapes are constructed with warp and weft threads in an over and under construction whereas knitted tapes are formed with a series of interlocking 'loops' like a knitted sweater.       

  • Which is better 'knitted' or 'woven' tape?

    Woven tapes are often less flexible than knitted tapes. It depends upon the application as to which is considered better. Knitted tapes are very soft and conformable. They bed down well and are  perfect for taping awkward shapes. Both woven and knitted tapes have their place.

  • How do I prevent the end of a glass fibre seal or tape from fraying when cut?

    We recommend the use of our adhesive backed glass cloth tapes for end sealing.

  • How many turns of adhesive glass cloth tape should I apply to the seal?

    We recommend one and a half turns as a minimum.

  • What can I use on the ends of the firesleeve when it is cut?

    We recommend our silicone rubber self-amalgamating tape to seal the end.

World Class Bespoke
Product Manufacturing

Why not give us a call to discuss how our existing selection of sealing and insulating products could be a good fit for your need. Our Pyroglass team is friendly, experienced and passionate about delivering a practical solution that best suits your needs.

CONTACT US

We want to hear from you


Our knowledgeable team have the resources and experience to advise you on the most appropriate solution that fits your needs. 
Send us your details and one of our engineers will contact you directly.

Contact Us

Our Products


We produce a variety of ready to use products suitable for many industrial and domestic applications. If you are looking for a one off solution, we can put you in touch with your nearest Pyroglass Distributor who can quickly fulfill your need. Alternatively if you are looking for a bespoke manufactured insulating or sealing product, we can provide a range of unique options that suit your business.

Looking for something else?

Share by: