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Designed to firestop the cavity behind external walls. Suitable for masonry and brickwork external substrates only.


CavGuard Roll 50 is a cavity fire barrier designed to firestop

the cavity behind external walls consisting of outer substrates of masonry or brickwork. The low smoke, zero halogen, highly expansive intumescent material allows ventilation to be maintained in non-fire conditions.

The CavGuard Roll 50 is made from a flexible intumescent material allowing it to be provided in a roll format. With a thickness of only 4 mm, the low profile design offers significant space and labour saving over traditional cavity socks, whilst also ensuring the external cavity is left

unobstructed and free to ventilate. It is also covered with a protective layer of polythene for ease of handling and to protect it from water.

In the event of a fire, the CavGuard Roll 50 intumescent material will expand to close the external wall cavity, providing effective fire resistance for up to 60 minutes depending upon the inner and outer substrates of the external wall system. The CavGuard Roll 50 is designed to close a free-air cavity of 46mm.

Features and benefits:

  • A fire-rated product, providing fire resistance performance within cavities and concealed spaces, for periods up to 60 minutes.
  • Ventilated design – developed to allow maximum ventilation of uninsulated cavities reducing the need for cavity trays or weepholes.
  • Suitable for ventilated cavities up to 50 mm wide.
  • Provided in rolls of 6.3 m long, 75 mm wide and 4 mm thick.
  • Flexible and lightweight - designed to be easily and quickly installed.
  • No maintenance required after installation.

General information






6300 mm


75 mm


4 mm


Pr_25_80_80_43 Intumescent sheet cavity barriersPrimary


P10/77 Ventilated cavity barriers

P10/435 Ventilated cavity barriers

Specification data - Intumescent sheet cavity barriers

General requirements

Insulation products generally.


Tested and certified in accordance with ASFP Technical Guidance Document TDG19.




4 mm.

Cavity width

50 mm.


CavGuard Roll 50

CavGuard Roll 50

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