Intumescent Seals is a division of Dixon International Group Limited


thermaglaze30 installed in glazed panel image

THERM-A-GLAZE 30 is a high pressure intumescent strip material which has been developed for glazing applications where a large amount of expansion is beneficial whilst retaining a firm pressure. The degree of expansion is more than 20 fold.


THERM-A-GLAZE 30 has been developed to provide excellent sealing properties combined with the benefit of a flexible strip of intumescent material. It is particularly useful in cases where there is a requirement for generous expansion properties. It expands to fill gaps forming a dense mat of impenetrable intumescent carbon.


THERM-A-GLAZE 30 intumescent strip is supplied at 10mm x 2mm as standard. It is a dry glazing material with a self adhesive backing to allow rapid and easy installation in glazed fire door apertures. The material can be cut with scissors or a sharp knife and so is very easy to fit to glazing beads.


THERM-A-GLAZE 30 is a flexible graphite based intumescent product giving an approximate twenty fold increase in volume when exposed to heat. Its activation temperature is around 200ÂșC. THERM-A-GLAZE 30 is supplied in a dark grey colour as standard and, because of its resistance to both atmospheric moisture and carbon dioxide, requires no additional surface protection. The material may be decorated with a wide range of conventional finishes without impairing the performance.

thermaglaze 30 image
  • 1. Glass
  • 2. THERM-A-GLAZE 30 (10 x 2mm)
  • 3. Hardwood glazing beads (min. density 650 kg/m3) 23mm wide by 23mm high incorporating a 5 x 5mm bolection return, chamfered by approximately 20°
  • 4. Non-combustible/hardwood setting blocks
  • 5. No.8 Screws, 50mm long at 150mm centres
  • 6. Nominally 44mm thick FD30 door leaf


Thermaglaze colour swatch image

THERM-A-GLAZE 30 is supplied as dark grey.*

Nominal sizes are available in the following dimensions:

  • 10 mm x 2 mm

And in standard lengths of 1050 mm or 2100 mm.

Lengths of up to 3000 mm are available on request.

* Colours may vary slightly between examples illustrated in print, online and actual examples - which will depend upon lighting conditions in situ.

Test Evidence

THERM-A-GLAZE 30 has been successfully tested as a component of various door sets to meet the fire resistance requirements of BS476:Part 20 & 22. It has also been certified to the more exacting standards required by Certifire. See Intumescent Seals certificate CF 284 on for details. It is currently being evaluated to the requirements of BS EN 1634-1.

Copies of test reports and assessment evidence are available on request.

Thermaglaze 30 - IFSA logo

Related Products

Improved glazing performance may be obtained by combining THERM-A-GLAZE 30 with other intumescent products in certain circumstances.

Please contact our Technical Department for further advice.