What are Firehoods? And when do you need them?
The primary purpose of a firehood is to maintain the fire integrity of a ceiling when ceiling speakers have been installed. As you can imagine, cutting large holes in a ceiling to accommodate speakers will destroy the fire barrier and as an installer you are responsible for maintaining that barrier when installing any equipment. It’s essential that you clue yourself up on where firehoods must be installed. We suggest that when in doubt, a firehood should be used.
It’s commonly accepted that firehoods are an absolute requirement when speakers are installed in a ceiling below a habitable room with a floor made from timber/chipboard etc. but where else must they be used? Our friends at Firetopper explain.
I'm installing speakers in a bedroom with only loft space above. Do I need to fit fire hoods?
There is some inconsistency between individual Building Control Officers on their interpretation of the regulations, but many are now insisting that all speakers are covered. All the major developers we dealt with as installers (Redrow, Taylor Wimpey, Bellway etc) insist on them on all speakers. The size of hole required for in ceiling speakers means that the ceiling's thermal, acoustic and fire rating is severely impaired and the thin paper cone of the speaker offers practically no remedy to the damage done.
If you are planning to install in ceiling speakers without hoods anywhere within a property, then permission should be sought from the relevant Building Control Officer.
If they agree to no hoods being fitted, we'd recommend you ask for this in writing and keep the document stored safely for future reference. We'd also recommend you ask the home owner to sign a Disclaimer of Responsibility which makes it clear that the owner accepts responsibility, and understand that in the event of a fire, any insurance claim could be affected.
I'm installing speakers in a pitched roof. Do I need to fit fire hoods?
As with the answer above, the installer has a responsibility to maintain the thermal properties of the structure. With a pitched roof you will typically have to cut approximately 2 cubic foot of thermal insulation away to accommodate the speaker causing a serious breach to the thermal properties of the ceiling. The thin cone of the speaker will do practically nothing to restore the ceilings thermal properties. The Firetopper Pro has a high level of thermal insulation due to the air trapped in the acoustic foam layer, restoring most of the thermal insulation lost by cutting away the Kingspan or other insulating material. We'd also recommend filling any remaining cavity cut away with Rockwool.
I'm installing speakers in a suspended ceiling with a concrete floor above. Do I need to fit fire hoods?
The first thing you need to find out is wether the void between the ceiling and the concrete floor above is a Plenum Space. Plenum spaces are the open spaces above the ceiling or below the floor that are used for air circulation. If the void is a Plenum Space, then yes, fire hoods will be required. If not, you'll still need to consider the other factors so again if you are planning to install in ceiling speakers without a hood, written permission should be sought from the Building Control Officer, and disclaimers put in place.
I'm installing in wall speakers in an internal stud wall do I need to fit fire hoods?
If the adjoining room forms part of a Fire Escape Route, then yes, fire hoods will be required. If not, then again seek advice from your building control officer and make sure you have your disclaimer in place.
Why should you be using firehoods on your installation?
- Maintain the fire integrity of a ceiling when installing speakers
- Reduce sound leakage to the room above
- Ensure you are in compliance with building regulations
If in doubt contact your Building Control Officer, the above article should be regarded as suggestions only.