Part 4 of the Building Regulations 2006

Requirements for Smoke Alarms/Detectors

Smoke Alarms must be installed in:

(a) Class 1a Buildings (Dwellings)
(b) Class 2, 3 and 4 Buildings being Units, Townhouses and residential parts of buildings
(c) Smoke Alarms must be connected to the consumer mains power (hard wired) where consumer power is supplied to the building, and are supported with an emergency back-up battery.

Location – Class 1a, 2, 3 and 4 Buildings

Smoke Alarms must be installed in a Class 1a Building on or near the ceiling in:

(a) any storey containing bedrooms –
i/ between each part of the Dwelling containing bedrooms and the remainder of the Dwelling; and
ii/ where bedrooms are serviced by a hallway, in that hallway, and
(b) any other storey not containing bedrooms.

Explanatory Information:

1. How does a Smoke Alarm work?

There are two types of Smoke Alarms.

1.1 Photoelectric:

This type of Smoke Alarm uses a light source and photocell. As the smoke enters the detection chamber it interferes with the light beam which in turn causes the alarm to sound.

1.2 Lonisation:

A small amount of radioactive material is used to create an electrical current which it travels through ionoised air. When smoke enters the detection chamber it impedes the flor of current and causes the alarm to sound.

2. Location of Smoke Alarms.

When deciding on the position of Smoke Alarms it is important to remember that they are intended to detect smoke before it reaches the sleeping occupants of a building.
The ensuring alarm is designed to wake the occupants and give them time to evacuate the building.

2.1 Protection of Sleeping Areas in Class 1a Buildings

The Regulations require that Smoke Alarms be located "between each area containing bedrooms and the remainder of the Dwelling". In some Dwellings the bedrooms are located in a common area and connected by a hallway. In this instance the Alarm should be located in the common hallway. It is a requirement of the Electrical Commission that Smoke Alarms be positioned to be within 1.5m of all bedrooms.

2.2 Location of the Smoke Alarm on other Storeys

A Smoke Alarm is also required on each other storey that is not already provided with a Smoke Alarm. It should be noted that Smoke Alarms are required to be installed in other storeys even if those storeys consist of only car parking, bathrooms, laundries and the like.

The favoured location for this alarm will be in the path of travel people will most likely take to evacuate the building. This will ensure an alarm will be raised before smoke makes the common exit path impassable. e.g. if the bedrooms are on the first floor, then an alarm should be positioned near the area of the inter connecting stair at ground level.

If the other storey is not connected to the remainder of the building (for instance a ground floor garage) then the alarm should be centrally located in the lower area.