Dead Air Space: Smoke Alarms Relocation Disclaimer

Relocation Disclaimer

*The current positioning of one or more smoke alarms fails to meet the requirements of section of the NCC 2019 Building Code of Australia (“BCA”) - Volume Two and as a result, the non-compliant smoke detector(s) in your property must be moved. Please note that when a Smoke Alarm is relocated or replaced, there may be residual damage either from the original installation or resulting from the relocation or replacement of the Smoke Alarm. Our technicians are not professional painters/plasterers but will make reasonable efforts to avoid causing further damage. Damage that may have been caused by the original installation or from the relocation or replacement can vary due to the type of original smoke alarm installed, the size of the cable hole and existing paint coverage and there may be discolouration from the original smoke alarm location or from plastering. If the smoke detector(s) are installed on a concrete ceiling our electrician will use conduit to reposition the smoke detector(s). Where you require repair, a quote for a professional plasterer/painter can be provided upon request. Any such work would be at your own additional cost.


Proper Positioning of Smoke Alarms

Smoke alarms need to be located on (or near) the ceiling for optimum detection of smoke in a fire situation with special care taken to avoid dead air spaces.


What is Dead Air Space?

A dead air space is an area in which trapped hot air will prevent smoke from reaching the alarm. This space generally occurs at the apex of cathedral ceilings, the corner junction of walls and ceilings and between exposed joists etc. (see diagram 1).

Smoke alarms may be located on the wall in accordance with Diagram 1 provides location criteria and the dimensional relationship to building elements and the associated dead air spaces.

Where a smoke alarm is located on the ceiling it must be—

  1. a minimum of 300 mm away from the corner junction of the wall and ceiling; and
  2. between 500 mm and 1500 mm away from the high point and apexes of the ceiling, if the room has a sloping ceiling.

Where (a) is not possible, the smoke alarm may be installed on the wall, and located a minimum of 300 mm and a maximum of 500 mm off the ceiling at the junction with the wall.

Diagram 1:


What do you need to do?

Detector Inspector has identified that one or more smoke alarms in your property fail to meet the requirements for proper positioning and need to be moved in order to avoid dead air space.

While Detector Inspector understands that the current positions of the smoke alarms may have been previously defined by a builder or qualified electrician in accordance with earlier standards, they, unfortunately, fail to meet the current standards.

This quotation is provided to get your consent to the required works. Once repositioned in accordance with the BCA, it will ensure the smoke alarms function as intended and are not affected by dead air spaces. Most importantly, this will mean that you will have exercised an appropriate duty of care to resolve a known issue with smoke alarm positioning.

If you do not wish to use Detector Inspector to complete this work, please ensure your chosen technician adheres to the BCA requirements set out above.

If you choose to leave the smoke alarms installed in their current location please indicate this on the quotation. We will then continue servicing the property as normal without relocating the alarm.

Important information to note

Please note that Detector Inspector will not take responsibility for the working order of the smoke alarms if they are found to not operate effectively due to being located in dead air spaces

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