Friday, 5 October 2012

What is a Fire Rated Downlight?

What is a Fire Rated Down Light?

The first of our recessed downlighter blogs is on the fundemental issue of what exactly is a fire rated downlight. We get many questions every day asking different questions so hopefully this will clear some of the confusion.

Firstly, a Fire Rated downlight does not mean that if the fitting catches fire it will not spread. This is probably the biggest misconception. We have never heard of a downlighter that has caught fire so this is a very rare instance which is probably due to the high level of checks and certifications the downlights need to have before they are put into production.

Put simply, a Fire Rated downlight acts as a fire door between the room that is on fire and the upper floors above the room. Fire will take the easiest route possible to spread, therefore having 10 or so holes in your ceiling will help the fire spread quicker, a bit like having no fire doors in a property and letting fire spread from room to room quickly.

What the Fire Rated Downlight does is act as a fire door, stopping the fire spreading to the floor above through the holes that the downlights sit in. Various makes and models have different times that they hold back fire for and the best ones are rated for 90 minutes. This means if there was a fire in the kitchen where the down lights were situated, the room above this would have protection from the fire coming through these holes for 90 minutes. This should be ample time for anybody to exit the building and the fire brigade to extinguish the fire.

How do the Downlights become Fire Rated?

240V Fixed firerated downlightsThe picture on the left shows a Fire Rated downlight. The two clips on it are what holds it into the ceiling. The can on the back will hold off the fire for 90 minutes. As well as this (although not pictured) there is an intumescent material circle around the lip of the downlight that would be pressed between the ceiling and the downlight. Intumescent material by nature swells when it is heated, this therefore causes a seal to be made around the downlight to stop any fire penetrating the edge of the down light.

 The picture to the right show a typical down light that is not fire rated. Here we can see that there is no can on the back to stop fire penetrating the light. The back of the can is completely open therefore letting air and fire through. There will also be no intumescent material around the outside ring of this meaning that fire would be able to penetrate the side of these fittings. In the case of safety, it is always better to try and install downlights that are fire rated, as this will reduce the risk to the room above.

Are there other benefits to Fire Rated Downlights?

 Absolutely, as well as protecting from fire, fire rated downlights are also rated to protect from noise and moisture. Clearly a hole in the ceiling will let noise through, so when you multiply that by 10 or even more, a large amount of noise can be transferred through the holes to the upstairs rooms. This can be particularly noticable if a bedroom is above a lounge and the TV is being played. Often the noise will transfer leaving the person upstairs with an annoying mumble of the downstairs TV. Fire Rated downlights are rated to reduce the amount of sound that can penetrate the fitting therefore keeping it quiter upstairs. This is known as 'acoustic rating.'

As well as noise, moisture can also travel through non fire rated downlights into the ceiling void. This is best being avoided as it can cause problems with damp and mould. This can be particuarly evident in kitchens and bathrooms. A Fire Rated downlight will prevent moisture from escaping into the cavity above the room.    

Are there different types of Fire Rated Downlights?

Yes, there are quite a few different types of Fire Rated downlights available today, these include IP65 Rated ones (for bathrooms), tiltable ones (for sloping ceilings), Low Energy and LED Versions and also tiltable bathroom downlights which can focus a light beam on the bath/shower etc whilst keeping moisture out of the downlight. Of course all of the halogen downlights can be dimmed which can create mood lighting.

Are there standards that I should look for?

Yes, the industry standards that should be met are as follows;

Part C compliant (stops moisture & air flow) Part E compliant (acoustic rating) Approved by Warringtonfire to BS476 (part 20/21/23) Approved by BPB to BS EN ISO 140-3&6 717-1&2. Tested in accordance with appendix F, edition 2 of robust interiors.

Are they any different to fit?

Fire rated downlights are one of the easiest lighting products to fit as they slot straight into the hole after they have been connected to the terminals. The majority are Double Insulated as well meaning that it doesn't matter if you have no earth connection. Any electrician will easily be able to fit these downlights into place.
How fire rated downlights look after being installed.

 The right hand picture is a quick in situ image showing how the downlights would look once installed. Recessed down lights are growing in popularity each year with many architects specifying recessed fire rated downlights on their projects.

To see a wide range of fire rated downlights that conform to all of the regulations please click here. 

Thank You for Reading

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