GTR Glazing Seal Roll – 20m is a flexible, self-adhesive intumescent foam glazing tape developed for use within approved glazed apertures in fire-resisting doors and screens.
The tape combines a highly compressible foam structure with graphite-based intumescent material.
During normal conditions, it provides a flexible bedding and sealing layer between the fire-resistant glass and the associated glazing bead or glazing-system component.
When exposed to elevated temperatures during a fire, the intumescent material expands to help seal the glazing pocket and protect the glazed aperture.
The stocked range is supplied in three profiles:
Every size is supplied as a 20m black roll.
GTR tape is intended for use as part of an approved fire-resistant glazing system in:
The tape is normally fitted around the glass or to the glazing beads in the position required by the tested glazing-system detail.
It should not be treated as a general-purpose glazing tape where fire performance is required without supporting evidence.
During a fire, the graphite-based material expands and forms an insulating char within the glazing pocket.
This expansion can help:
The manufacturer states that expansion begins at approximately 180°C and can reach around three to four times the tape’s original volume.
Its expanded char is designed to remain stable under high-temperature fire conditions.
GTR differs from a rigid intumescent glazing strip because it incorporates a flexible foam structure.
The tape can:
The standard tape is 5mm thick and can be compressed to approximately 2mm where the approved glazing-system detail requires that degree of compression.
The tape must not be compressed beyond the requirements of the tested system.
The product is described as a low-to-medium pressure intumescent glazing tape.
This means its expansion is intended to develop sealing pressure without applying the much higher forces associated with some rigid graphite products.
This characteristic can be useful around fire-resistant glass, where uncontrolled pressure could affect:
The correct tape size, compression and glazing-pocket dimensions must still follow the applicable fire-test evidence.
GTR incorporates a strong self-adhesive backing to assist installation.
The adhesive holds the tape in position while:
The adhesive is an installation aid only.
It does not structurally retain the glass or replace the glazing beads, pins, screws, setting blocks or other components required by the tested glazing system.
The flexible tape can be cut with sharp scissors or a suitable knife.
This allows it to be fitted accurately around:
Cuts should be clean and square, with adjoining tape sections fitted closely together.
Open joints can leave an untreated route through the glazing seal.
GTR has been developed primarily for supported:
The tape does not possess a universal standalone fire rating.
The permitted performance depends on the complete glazed construction, including:
The required fire period must be supported by evidence for the complete glazing system rather than by the tape alone.
The manufacturer describes the product as suitable for a broad range of fire-resistant glazing applications, including systems using:
Compatibility must be confirmed for the particular glass product and glazed construction.
Do not assume that GTR tape can be used with every fire-resistant glass solely because the required fire period is the same.
Before using GTR within a fire door, confirm that the door’s evidence permits:
Cutting glazing into an existing certified door without supporting evidence can invalidate the door’s fire classification and certification.
GTR glazing tape is supplied in one colour:
Black
The tape will normally be largely concealed behind the glazing beads once installation is complete.
A narrow exposed sightline may remain depending on:
Do not paint the tape or apply decorative coatings to the intumescent surface.
The stocked options are:
The width should be selected according to the tested glazing-system specification.
A wider tape is not automatically a higher-rated alternative, and the three profiles should not be substituted without evidence.
Each product is supplied as a continuous:
20-metre roll
The roll format allows installers to cut the required lengths for each side of the glazed aperture.
The quantity required depends on:
Measure the complete glazing perimeter before calculating the required number of rolls.
GTR tape must not be relied upon to carry or retain the weight of the glass.
The complete glazing system may require:
Every structural and fire-protection component must match the tested or assessed system.
The product is designed primarily as an intumescent fire-glazing tape.
It should not automatically be assigned:
Any smoke or acoustic performance must come from evidence for the complete glazed door or screen assembly.
Subject to the applicable test evidence, GTR may be used within glazed constructions in:
Before ordering, confirm:
Do not select the tape width solely according to the available space within the glazing pocket. The selected profile must match the tested or assessed glazing system.
GTR Glazing Seal Roll is a self-adhesive graphite-based intumescent foam tape for use within approved fire-resistant glazing systems.
| Product Name | GTR Glazing Seal Roll – 20m |
| Manufacturer Product Name | Sealmaster Intumescent Foam Glazing Tape |
| Product Reference | GTR |
| Product Type | Flexible intumescent fire-glazing foam tape |
| Application | Glazed apertures in approved fire-resisting doors and screens |
| Material | Graphite-based intumescent foam tape |
| Foam Type | Flexible, highly compressible foam |
| Intumescent Pressure | Low-to-medium pressure |
| Fixing | Single-sided self-adhesive backing |
| Available Widths | 10mm, 15mm and 20mm |
| Uncompressed Thickness | 5mm |
| Published Compression | Can be compressed to approximately 2mm where required by the approved glazing system |
| Roll Length | 20m |
| Colour | Black |
| Activation Temperature | Expansion begins at approximately 180°C |
| Published Expansion | Approximately three to four times its original volume |
| Published Thermal-Erosion Resistance | Char stability stated beyond 900°C |
| Fire-Test Standards Referenced | BS 476-22 and BS EN 1634-1 |
| Typical Supported Fire Applications | 30-minute and 60-minute glazing systems, subject to complete test or assessment evidence |
| Certifire Reference | CF5387; current certification status should be confirmed before reliance |
| Current Accessible Certificate Expiry | 13 May 2026 |
| Structural Glass Retention | No — glazing beads, fixings and setting blocks are required as specified by the complete system |
| Standalone Fire Rating? | No — performance applies only as part of a tested or assessed glazing assembly |
| Standalone Smoke Rating? | No specific standalone cold-smoke classification is stated |
| Standalone Acoustic Rating? | No |
| Width | Thickness | Roll Length | Colour | Product Code |
|---|---|---|---|---|
| 10mm | 5mm | 20m | Black | GTR/10X5FM |
| 15mm | 5mm | 20m | Black | GTR/15X5FM |
| 20mm | 5mm | 20m | Black | GTR/20X5FM |
The manufacturer’s general code structure is:
GTR + Size + FM
The exact stocked codes use the following supplier format:
| Size Options | Length Options | Colour Options | Total Variations |
|---|---|---|---|
| 10 × 5mm, 15 × 5mm and 20 × 5mm | 20m | Black | 3 |
The required profile must be selected from the tested glazing-system detail.
The 10 × 5mm tape provides the narrowest stocked face width.
The 15 × 5mm tape provides an intermediate width.
The 20 × 5mm tape provides the widest stocked face width.
Do not assume that:
GTR tape has been developed for use within fire-resistant glazing systems, particularly those designed for 30- and 60-minute applications.
The actual performance depends on:
No fire period should be assigned to the tape in isolation.
Current product pages continue to reference Certifire CF5387.
The accessible certificate record states that the certificate was within its expiry date until 13 May 2026.
Before using CF5387 for a current project, obtain confirmation of:
The integral adhesive is intended to retain the tape during assembly.
The adhesive must not be treated as:
The published technical data states that the 5mm tape can be compressed to approximately 2mm where required.
The required compression must be controlled by:
Excessive compression can distort the glazing assembly, while insufficient compression may leave localised gaps.
Store the rolls:
Before installation, reject or replace tape that is:
GTR Glazing Seal must be installed as part of an approved fire-resistant glazing system.
The glass, glazing beads, setting blocks, fixings, aperture dimensions, tape profile and installed compression must all match the applicable fire-test or assessment evidence.
Do not cut a glazed aperture into a fire door or screen until the complete specification has been confirmed.
Typical tools and components may include:
Confirm:
Do not substitute components without written supporting evidence.
Read the complete glazing detail before preparing the aperture.
The evidence should identify:
Where these details cannot be established, do not proceed.
Check that the prepared glazed aperture is:
Machining a certified fire door outside the permitted detail can invalidate its evidence.
Where the tested system requires an intumescent or fire-resistant aperture liner, install it before fitting the glass and beads.
The liner must:
Do not add or omit a liner unless the glazing-system evidence permits it.
Cut and prepare the glazing beads according to the approved system.
Confirm:
The bead faces receiving the adhesive tape must be clean, dry and stable.
Remove:
The self-adhesive backing requires continuous contact with a clean surface.
Confirm whether the approved arrangement requires the GTR tape to be applied:
Do not assume that the same tape position applies to every fire-glazing system.
Measure the first side of the glazed aperture or glazing bead.
Transfer the measurement to the tape without stretching it.
The tape should be long enough to meet the adjoining section closely at the corner.
Cut the GTR cleanly using sharp scissors or a suitable knife.
The cut should be:
Do not pull or stretch the tape while cutting.
Peel back a short portion of the release liner.
Align the tape in the required position and press the adhesive face firmly against the prepared surface.
Continue removing the liner progressively while applying the tape.
Do not:
Measure, cut and apply the remaining sections.
At each corner:
The tape should form a continuous sealing line around the complete aperture.
Inspect the installed tape for:
Correct defects before the glass is installed.
Position the approved glazing setting blocks exactly as required by the tested system.
Setting blocks support the glass and maintain the required clearance within the aperture.
Do not use the GTR tape itself to carry the weight of the glass.
Using suitable glass-handling equipment, place the approved glass into the prepared aperture.
Check that:
Do not allow the glass edge to cut through the tape.
Where the system requires GTR on both sides of the glass, install the opposing tape in the specified position.
Maintain:
Position the glazing beads carefully around the glass.
The beads should compress the GTR evenly without:
The final tape thickness must match the approved glazing arrangement.
Secure the glazing beads using the specified steel pins or screws.
Follow the tested system for:
The self-adhesive tape does not replace these mechanical fixings.
Inspect the visible tape line around the aperture.
The compression should be:
Do not rely solely on visual appearance where the specification requires a measured glazing-pocket dimension.
Check all four corners on both faces where applicable.
The tape and beads should:
Remove loose dust and installation debris.
Do not use cleaning chemicals that may:
Do not paint over exposed GTR tape.
Confirm that:
Record the glass, tape and glazing-system references where the doorset is subject to certification or inspection.
Inspect the glazed aperture as part of the fire-door or fire-screen maintenance programme.
Check for:
Damage to any component may affect the performance of the complete glazed assembly.
GTR tape does not independently provide a fire-resistance period.
The performance of the installation depends on the complete approved system, including:
Install the product only in accordance with current test evidence, assessment documentation and the instructions applicable to the complete glazed construction.
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