The Ultimate

Solution for Void

Fire Detection

Voidalert Voide Fire Detection System

Void detection is a fraught issue, especially on new-build projects.

From a design perspective it is difficult to predict the amount of detection required and invariably, providing access for ongoing maintenance is a challenge.

VoidAlert TM heat sensitive sensor-wire is installed through the protected area between the VoidAlert TM Remote Indicator and VoidAlert TM Test Point. The Test Point is typically installed in an accessible location to facilitate ongoing engineer maintenance.

Voidalert Voide Fire Detection System Remote Indicator

The VoidAlert TM ‘Test-Point’ incorporates a keyswitch with ‘normal’ and ‘test’ positions. Operation of the key switch tests the system for both ‘Open Circuit’ and ‘Fire’ conditions. In order to fault test the sensor-wire, the ‘test’ mode key position is selected and a simulated fire signal is generated to activate the Fire Alarm System. VoidAlert TM can be interfaced with all types of Fire Alarm System including conventional and addressable.


The VoidAlert TM Remote Indicator illuminates when the system is activated.

Voidalert void fire detection system Test Point

British Standard Design requirements...

  • Install AFD to voids greater than 800mm
  • Treat downward projections exceeding 10% of the void depth as walls

22.2d) If the system Category is such that automatic fire detection should be provided in any area that contains a horizontal void of 800 mm or more in height, automatic fire detection should also be provided in the void.

22.3j) Ceiling obstructions, such as structural beams, deeper than 10% of the overall ceiling height should be treated as walls.

NOTE 10 Within horizontal voids, beams or obstructions that are deeper than 10% of the overall depth of the void regardless of whether the void is above the ceiling or below the floor, ought to be treated as walls that subdivide the void.

VoidAlertTM is a brand of Avansys

Avansys LLP

West Midlands (Head Office)

Mayflower House, Bodmin Road, Coventry CV2 5DB

Tel: +44 (0)24 7661 6699   Fax: +44 (0)24 7662 1990

© Avansys LLP. Regisered in England and Wales No. OC384483