Whether or not every downlight has to be fire rated is a straightforward issue with an obvious answer: no. Everything relies on how the building is built overall and the ceiling into which the downlight will be inserted. To guarantee that fire and excessive heat are kept out of cavities, Electrical Safety First advises the use of "fire-rated" downlights equipped with aluminum reflector bulbs for all downlights put into ceilings. Legally, the Building Regulations must be followed for all construction projects in England and Wales. Section B and the Approved Document both address fire safety. Let's look at fire rating as a whole, when it is necessary, why it is necessary, and what the testing criteria are.
Why is the fire rating necessary?
In the UK, a typical home has two storeys, and when there is living space above, the plasterboard ceiling and timber floor structure must pass rigorous fire testing. In these buildings, the entire floor/ceiling construction between the two floors must withstand a minimum of 30 minutes of fire in order to: a) prevent rapid fire spread that could trap building occupants; b) lessen the likelihood that fires will grow large because large fires are more dangerous to building occupants, fire and rescue service personnel, as well as people nearby.
No fire rating is necessary if there is no living area above, such as a loft. But, if the fire were to spread and endanger the building's security and roof structure, we would still advise using fire-rated downlights. The more storeys in a building, the longer the fire protection/ compartmentation needs to endure. For instance, the whole ceiling/floor structures in a three-story building with a loft converted to a bedroom must meet a minimum 60-minute fire rating to provide time for people to escape in the case of a fire.
Fire rating and downlights
The floors and ceilings will have passed fire inspections as a whole, but the fire barrier is damaged once an aperture is formed for a downlight. A typical open back downlight enables heat, smoke, and flames to enter the floor area, increasing the risk of a collapse before the requisite 30, 60, or 90 minutes have passed. A downlight that is fire-rated has a sealed steel body and an external intumescent strip around the fixture. These components act as a barrier between the room and the ceiling void in the event of a fire, delaying the spread of flames for a while. The intumescent substance aids in preventing the spread of the flames, heat, and vapours into the space.
