Can I just fit heat alarms instead of smoke alarms

[Adsibob]

I have a very open plan layout at ground floor which caused our BCO to insist we get a fire engineering report.

 The report requires us to get a sprinkler system and also to do this:

 I have found a BS 5839 part 6 Grade D2 mains powered interlinked fire alarm which I like because it is quite small and unobtrusive, but it is a heat alarm not a smoke alarm. I think these go in the kitchen normally, but any reason why all the alarms in my house can’t be of this heat detection type, rather than smoke?

[Temp]

As I understand it smoke alarms give you more time to escape. I think heat alarms need line of sight to the fire?

[Temp]

https://www.safelincs.co.uk/a-summary-of-the-bs5839-6-2019/

 

 

Quote

For kitchens and garages, dedicated detectors are available called heat alarms. As the name suggests, they operate by detecting abnormally high temperatures in their surroundings. Because of how they work they are immune to the typical causes of nuisance alarms like burned toast, steam from cooking, or dust. However, they cover smaller areas than a smoke alarm and take longer to be triggered by common household fires, so are not usually used in any other rooms.

 

 

Edited March 6, 2022 by Temp

[Adsibob]

I guess I’m just wondering what the legal requirement is. The report says “fire detection and alarm system”, so I’m just wondering whether compliance would be satisfied with a heat alarm system. We have a large open plan area off the kitchen, and given the toaster in the kitchen and the wood burning stove at the other end of the open plan space, the potential for false alarms is fairly high. I was therefore thinking of installing the majority of the alarms on the ground floor as heat alarms. Happy to have smoke alarms on the upper floors.

[JohnMo]

Not sure where you live.

 

But in Scotland, you have to have a heat alarm in a kitchen area, you cannot install a smoke alarm.

 

Every home must have:

 

one smoke alarm in the living room or the room you use most

one smoke alarm in every hallway and landing

one heat alarm in the kitchen

All smoke and heat alarms should be mounted on the ceiling and be interlinked.

 

If you have a carbon-fuelled appliance – like a boiler, fire, heater or flue – in any room, you must also have a carbon monoxide detector in that room, but this does not need to be linked to the fire alarms.

 

If an area is open plan, one alarm can cover the whole room provided it can be located where it is no more than 7.5 metres from any point in the room. If your space includes a kitchen area it should be a heat alarm rather than a smoke alarm

[Adsibob]

4 minutes ago, JohnMo said:

Not sure where you live.

 

But in Scotland, you have to have a heat alarm in a kitchen area, you cannot install a smoke alarm.

 

Every home must have:

 

one smoke alarm in the living room or the room you use most

one smoke alarm in every hallway and landing

one heat alarm in the kitchen

All smoke and heat alarms should be mounted on the ceiling and be interlinked.

 

If you have a carbon-fuelled appliance – like a boiler, fire, heater or flue – in any room, you must also have a carbon monoxide detector in that room, but this does not need to be linked to the fire alarms.

 

If an area is open plan, one alarm can cover the whole room provided it can be located where it is no more than 7.5 metres from any point in the room. If your space includes a kitchen area it should be a heat alarm rather than a smoke alarm

I live in England.  I will call the fire engineer that charged us an arm and a leg for a cut and paste job and see if I can get some more information. 

[ProDave]

1 hour ago, Adsibob said:

I guess I’m just wondering what the legal requirement is. The report says “fire detection and alarm system”, so I’m just wondering whether compliance would be satisfied with a heat alarm system. We have a large open plan area off the kitchen, and given the toaster in the kitchen and the wood burning stove at the other end of the open plan space, the potential for false alarms is fairly high. I was therefore thinking of installing the majority of the alarms on the ground floor as heat alarms. Happy to have smoke alarms on the upper floors.

We have a heat alarm in the kitchen and a smoke alarm in the adjacent hall, and the smoke alarm has never triggered even when cooking with the doors open.

[nod]

My understanding would be that a smoke and heat alarm serve two different purposes 

Smoke alarm will warn you of smoke 

If your heat alarm goes off U you our kitchen is almost certainly on fire 

[TonyT]

Ask your local authority what they want,

 

are you using mains cabling type, battery or fire alarm based system?

 

who is designing the M&E system?

 

did the ‘Architect’ come up with a fire strategy?

 

Edited March 6, 2022 by TonyT

[ProDave]

8 hours ago, Adsibob said:

I have a very open plan layout at ground floor which caused our BCO to insist we get a fire engineering report.

 The report requires us to get a sprinkler system and also to do this:

Can you tackle this another way?  Find out what you would need to do to make it less "open plan" so BC would accept conventional domestic smoke alarms and see if you can find a compromise.  Remember you are not obliged to actually shut a door so would a partition with a pair of sliding pocket doors satisfy BC yet still leave it open plan enough for you with both doors slid into their pockets?

[Jilly]

Having watched a fire take hold in my neighbour's kitchen extension, I would say downstairs smoke alarms are essential, away from the toaster end or whatever.  By the time we all realised what was happening, flames were near the top of the building. This was daytime, with everyone wide awake. It took much less than 5 minutes. What you are proposing means that your downstairs would be properly on fire before the smoke alarms tripped at night. Is that really what you would want?

 

[ToughButterCup]

11 hours ago, Adsibob said:

...but any reason why all the alarms in my house can’t be of this heat detection type, rather than smoke?

 

Yes.

The answer to your problem is really simple: the types of fire detection are a matter for a competent designer . How those detectors look  isn't (because they in turn will have been designed by competent designers). i.e. there are a range of sensor designs from which to choose 

 

• commission the fire engineering report 
• send the fire engineer your architects plans in relation to fire suppression
• send a copy of the fire engineers report to the BCO for approval - and wait for the response from his office
• meanwhile: send a copy of the report to two or three fire systems suppliers and ask them for a price to supply and fit (VAT NOT CHARGED ON SUPPLY AND FIT)
• Read the BCO's response to the design. If it varies from the design that you have commissioned , send the BCOs response to the fire company. Do not pay them anything until the BCO and the company have come to some form of agreement.
• Do NOT just fit what the fire equipment company says : the BCO can (and in our case did) reject the company's design and require additional protection. After it had been fitted. Cue noises from one AnnoyedButToughButtercup
• After doing Due Diligence, ask the suppliers to fit equipment which you want (that may well mean leg-work looking for unobtrusive equipment of the right type for your fire design)

 

Yes, what am saying is, that a nominally Competent Designer (as defined in CDM2015 as amended) official design can be challenged by a BCO ( he / she  won't sign your house off). And that has happened to us.  And, a year later, I'm still trying to unpick the problems caused.

 

Can't take a joke? Don't self-build. 

Edited March 6, 2022 by ToughButterCup

[Adsibob]

7 hours ago, Jilly said:

Having watched a fire take hold in my neighbour's kitchen extension, I would say downstairs smoke alarms are essential, away from the toaster end or whatever.  By the time we all realised what was happening, flames were near the top of the building. This was daytime, with everyone wide awake. It took much less than 5 minutes. What you are proposing means that your downstairs would be properly on fire before the smoke alarms tripped at night. Is that really what you would want?

 

I’m spending a small fortune on a sprinkler system, so I doubt it would ever get anywhere near as bad. Also, downstairs there would still be 3 smoke alarms, I’m just wondering if in the main lounge area I can swap the smoke alarm for a heat alarm, so that the open plan area was mainly served by heat alarms rather than smoke alarms.

[Radian]

11 hours ago, Adsibob said:

We have a large open plan area off the kitchen, and given the toaster in the kitchen and the wood burning stove at the other end of the open plan space, the potential for false alarms is fairly high

The wood burning stove shouldn't be an issue if working properly. Combustion products shouldn't be escaping into the air inside. I have an open fire that we throw logs onto and the nearby smoke alarm has yet to be triggered by it. The toaster, however, is the one appliance that never seems to be sufficiently well engineered. You might consider an extraction system specifically for this device but that's pretty extreme. One of my little projects is a hacked toaster that uses a PM2.5 sensor to trip the power when it gets the tiniest whiff of smoke. Perfect toast whatever the conditions and no more false alarms.

[Nickfromwales]

18 hours ago, Adsibob said:

The report requires us to get a sprinkler system

Does this requirement actually not read "automatic fire suppression system"?

[Adsibob]

26 minutes ago, Nickfromwales said:

Does this requirement actually not read "automatic fire suppression system"?

I've pasted directly from the report in the OP. Here it is again:, this is separate to the requirement to have a sprinkler system (which is a separate part of the report and which I've already installed).

[TonyT]

https://www.aico.co.uk/wp-content/uploads/2021/06/Ei3024-Ei3016-Ei3014-Instructions-1-1.pdf

 

for some good reading
 

 

heat in kitchen

smokes in hallways/landing.

 

and or follow JohnMo previous post. In adding to living room etc

 

if in doubt run 3core and earth to points and leave an unbroken loop behind the plasterboard for future use

 

Edited March 6, 2022 by TonyT

[Adsibob]

6 minutes ago, TonyT said:

https://www.aico.co.uk/wp-content/uploads/2021/06/Ei3024-Ei3016-Ei3014-Instructions-1-1.pdf

 

for some good teasing 
 

 

heat in kitchen

smokes in hallways/landing.

 

and or follow JohnMo previous post. In adding to living room etc

 

if in doubt run 3core and earth to points and leave an unbroken loop behind the plasterboard for future use

 

I know these are well reviewed, but I find them rather ugly. The Cavius are about half the size for mains powered or a quarter the size for battery operated. Unfortunately mine need to be mains powered, otherwise I'd be going for the tiny cavius battery operated ones.

[TonyT]

Personally I think the cavius ones are deeper so Will protrude more from the ceiling and look more obvious

 

aico for me all the time

Edited March 6, 2022 by TonyT

[dpmiller]

who gives a feck what they look like if they save your life?

[Adsibob]

1 hour ago, TonyT said:

Personally I think the cavius ones are deeper so Will protrude more from the ceiling and look more obvious

 

aico for me all the time

????

Cavius = 97mm diameter by 52mm height (volume = 384,311 mm3)

aicos = 150mm diameter by 66mm (volume 1,166,316mm3).

 

So the Cavius is less than 3 times smaller than the aicos

Edited March 6, 2022 by Adsibob

[Nickfromwales]

54 minutes ago, Adsibob said:

????

Cavius = 97mm diameter by 52mm height (volume = 384,311 mm3)

aicos = 150mm diameter by 66mm (volume 1,166,316mm3).

 

So the Cavius is less than 3 times smaller than the aicos

Visual impact of the lesser diameter vs nearly the same depth = a smoke detector that does look like it sticks out a lot more as the shape doesn’t lend itself to being inconspicuous imho. 
Forst glance and I thought “ceiling tit”. 
Aico for me still, sorry, but thanks for the alternative suggestion.   

[Nickfromwales]

9 hours ago, Adsibob said:

I've pasted directly from the report in the OP. Here it is again:, this is separate to the requirement to have a sprinkler system (which is a separate part of the report and which I've already installed).

I meant in respect of the sprinkle system. It seems to be a knee-jerk, by some less versed individuals, to use the term sprinkler system where it should actually read automatic fire suppression system, which allows a sprinkler OR mist system to satisfy this requirement.

 

For any areas where you may get false alarms, eg a smoke detector directly adjacent to / off a kitchen ( open plan area ), you can use an optical smoke detector vs an ionisation detector to reduce false triggers.

 

"Ionisation alarms are very sensitive to cooking vapours and if placed near a cooker or toaster are likely to give frequent false alarms. Optical alarms detect larger particles of smoke, the kind that are produced by a slow smouldering fire before it bursts into flames."

 

This will be as good an option as you can get to mitigate the issue, and what I've done for many previous M&E clients. It's something that any decent designer should have implemented as standard in any such proposal TBH.

[ToughButterCup]

9 hours ago, dpmiller said:

who gives a feck what they look like if they save your life?

 

Some people. 

[Marvin]

Ah! The old function versus form dilemma!