BS-5839 part 6 LD3

Dwelling fires are still falling in England from 28,504 in 2019/2020 to 25,408 in 2024/2025. That said the number of fatalities is creeping up 194 in 2024/2025 compared to 166 in 2023/2024 and 199 in 2022/2023

(source assets.publishing.service.gov.uk/.../FIRE0205.xlsx)

The guidance that supports the building regulations ADB v1 still up to 2029 only requires LD3.

BS 5839-6 does recommend a risk assessment before picking a category. And categories are short hand not straight jackets adding a extra detector does mean its becomes another category.

BS 5839-1:2019 + A1:2020 recommends LD2 for new dwellings. Plus it is starting its review in January so start your ideas on how it should be changed now!

What is the cost/value of the/a person for an average 3 bed semi against £150.  Remember, people are not just values or numbers, they are someones family or loved ones.

So for say, 20 million houses in the UK (there may be more by now) that's £ 3 BILLION - what could be done with that sort of money? Cure for another cancer? Thousands of urgent operations brought forward? Better care for the elderly? Are you going to tell their loved ones that they're less worthy than a plastic box on loads of people's ceiling's that 99.99% of the time provides no benefit whatsoever?

No easy answers.

  - Andy.

Will Lloyd said:

(source assets.publishing.service.gov.uk/.../FIRE0205.xlsx)

The link did not work for me, but I think that I have found the data.

I was going to ask how many of you have experienced a building fire, but ...

25,000 fires per year does not seem a huge number. However, given that there are 50-odd million of us, and allowing for an average household of two, that is a chance of being in a dwelling on fire in any year of approximately 1:1000, or 1:20 over 50 years.

I have had my experience! In fact the fire was in the landlord's quarters in my local (as in next door) pub about 45 years ago. If there was an alarm system, it was not installed there. When the alarm was raised - smoke was pouring out of the bedroom window - I dashed upstairs with a fire extinguisher, but the fire was way beyond that.

Happily, nobody was injured and rather unexpectedly, the pub was open for evening service.

No alarm would have made any difference, but the 2nd floor was used for B&B accommodation, and IIRC, any escape route would have been past the bedroom door.

I think that in this instance, LD2 would not have helped, but LD1 could have made a difference.

Back to Will's data: a drop of a third in the number of fires over 15 years seems impressive. However, as with the reduction in mortality due to stroke and heart attack, it may have more to do with the reduction in smoking rather than any other intervention.

I am not sure why it would cost the government or the people £ 3 BILLION.  As I stated previously you could get the kit from ScrewFix (other sellers are also available) for an interlinked system for between £100 to £200 for the average 3 bed semi 

 Afraid that Andy's figure seems to assume that nobody has any smoke detectors/alarms yet!

HMG promises to build (i.e. hoping that the private sector will build) 1.5 million homes during its 5 years in office. So at £150 a pop, that is £225 million.

One really good jackpot in the Lottery!!!

So the parts alone are £200, what does it cost to retrofit to a building and then make good ? I presume perhaps a day, maybe two, so more like 300-400 all up.  So we do that for 20 million house-holds and that is 20*300 = 6000 million, maybe 20*400 - 8000  so between  6-8 billion. You are right - it would be a serious investment.

Could we save enough extra  lives over the life of such an investment  (perhaps 10-20 years) compared to that money spent another way?  After all the folk dying from all the other things we don't do instead so we can afford to do just this are also someone else's loved ones. There is no truly free lunch. 

I'm not saying we should not uplift the recommended standards - far from it,  just that there is an argument for putting our money most carefully where it has most effect  - cost benefit analyses are not some obscure excuse not to do things, they do serve a very real purpose. We do need to be able to clearly justify why a more complex and expensive recommendation is to be preferred.

To my mind Chris's thought experiment is correct, but very hard to sell morally.

Mike. 

Afraid that Andy's figure seems to assume that nobody has any smoke detectors/alarms yet!

As a first approximation yes. But then consider that most alarms seem to come with a recommendation to replace after 7-10 years ... so you might then see the £3B as being less of a one-off investment, but an every decade recurring cost.

   - Andy.

The current government (Labour) came into power July 2024 with the ambition of 1.5 million new homes during their term in parliament.  The next general election must be called by August 2029. The general election MAY be called earlier.  I very much doubt they(Labour) or any UK government can achieve this objective during A/The 5 year Parliamentary term.  This point is however mute in this discussion as all new design and builds for domestic dwellings need/will need to meet an LD2 category due to
BS7671
BS5839
Building regulation and Approved Documents.  

The LD3 category would only really affect the existing housing stock in the UK except for Scotland.  Now of that, roughly 25 million housing stock in England about 1/3 are rented.  Thus they will/SHOULD be covered by things like PRS (Private Rented Sector) and social housing.

New builds only have to meet LD3 as that all the approved document requires (England) and the approved document has been 

revised with current revisions going up to 2029 I cannot see this changing anytime soon

In the simplest form you could have a battery power smoke alarm with RF interlink upstairs on the landing, the same downstairs near the front door and a heat alarm/sensor in the kitchen.  By choosing battery powered with RF interlink it means that each unit only really needs to 2 to 4 screws and the same amount of Raw plugs (other brands of fixing are also available).  Then upto 2 hours of labour to install and commission.

The caveat that most people forget is that the domestic smoke alarm / heat alarm / multi sensor alarm is only valid for 10 years max.  After this the sensor is deemed no longer accurate by the manufacturer.

Overall the cost is not that much for the average household/family living in the average 3 bed semi that they own/mortgage.

Will Lloyd said:

New builds only have to meet LD3 as that all the approved document requires (England) and the approved document has been 

revised with current revisions going up to 2029 I cannot see this changing anytime soon

The Approved Document is slightly ambiguous. Paragraph 1.1: All dwellings should have a fire detection and alarm system, minimum Grade D2 Category LD3 standard, in accordance with the relevant recommendations of BS 5839-6.

The phrase, "all dwellings" includes existing and new buildings. Whilst Table 1 of BS 5839-6:2019+A1:2020 lists LD3 for some existing premises, the minimum for new or materially altered premises is LD2.

So, I interpret the Approved Document as recommending at least LD2 for new builds.

Will Lloyd said:

New builds only have to meet LD3 as that all the approved document requires (England) and the approved document has been 

revised with current revisions going up to 2029 I cannot see this changing anytime soon

The Approved Document is slightly ambiguous. Paragraph 1.1: All dwellings should have a fire detection and alarm system, minimum Grade D2 Category LD3 standard, in accordance with the relevant recommendations of BS 5839-6.

The phrase, "all dwellings" includes existing and new buildings. Whilst Table 1 of BS 5839-6:2019+A1:2020 lists LD3 for some existing premises, the minimum for new or materially altered premises is LD2.

So, I interpret the Approved Document as recommending at least LD2 for new builds.