Smoke alarm on own mcb?
- Thread starter hard-work
- Start date
Sponsored Links
the recommendation from BS5839-6 for grade D is
Clause 15.4...
The normal supply for smoke alarms and any heat alarms in a Grade D system should be derived from the public electricity supply to the dwelling. The mains supply to the smoke alarms and heat alarms should take the form of either:
So can the alarm and lights be on the same rcbo?
Clause 15.4...
The normal supply for smoke alarms and any heat alarms in a Grade D system should be derived from the public electricity supply to the dwelling. The mains supply to the smoke alarms and heat alarms should take the form of either:
i) an independent circuit at the dwelling's main distribution board, in which case no other electrical equipment should be connected to this circuit (other than a dedicated monitoring device installed to indicate failure of the mains supply to the smoke alarms and any heat alarms); or
ii) a separately electrically protected, regularly used local lighting circuit.
ii) a separately electrically protected, regularly used local lighting circuit.
So can the alarm and lights be on the same rcbo?
Last edited:
I am not aware of any such requirement, but otehrs might know more than I do.
The wisdom of various approaches is often discussed, with some feel that having alarms, freezers etc. on 'constantly used' circuits (like a lighting one) means that one will more rapidly become aware that the circuit has 'failed' for some reason than if there is a dedicated circuit. The contrary argument is that the circuit is probably more likely to 'fail' if it is also being used for other purposes (and/or shares RCD protection with other circuits).
In the case of smoke (and other) alarms, they will have battery back-up and also will often give an indication (audible and/or visual) of power failure, which makes things a bit less crucial.
Kind Regards, John
Sponsored Links
I would presume so, since section 1.19 of "Approved Document B" (guidance relating to 'Part B' of the Building regs) says exactly the same as you have quoted BS5839-6 as saying.
Others may have more experience of this than I do.
Kind Regards, John
Well if they are not, tell them they are wrong and refer them to clause 15.4 above.
It is not uncommon for jobsworth at BCO to be wrong. Enlighten them and watch them walk away with their tail between their legs.
I have done with Gassafe men. Not difficult to do with them. One was insistent that a 38kW combi was too big in a flat. I had to explain that the boiler's output to the rads could be set to the heat demands of the flat and the 38kW went on a full belt for DHW. Another never the regs to inspection hatches in flue ducts. That was true. Another was a BCO who was insistent that a flat could not have the hall and kitchen made into one, saying fire doors are needed. I pointed out the 9 metre rule. He mmmed and never questioned it again. I find that BCOs are conscience of drains. Always have lots of rodding points where you can (do not put in elbows, put in tess with a rodding point), the odd AAV valve and waste non-return valve when in flats and they think `they know what they are doing`. Many builders are not well up on services and try to hide them. The BCOs like good services and attention to them with ease of maintenance.I suspect that they would be more impressed by a reference to 1.19 of App Doc B, since they worship the Building Regs, not Bristish Standards!
Kind Regards, John
Indeed, but it gets a bit messy, which confuses some people:
1... The Approved Documents are just guidance, not law, and the law itself (the Building Regs) is usually very vague, and some of the Approved Docs are not much less vague (Approved Doc P is an extreme example - see below).
2... The Approved Docs (and, in some cases, the Building Regs themselves) often refer to Standards, but do not necessarily 'demand' (not that they could, since they are not law) compliance with them.
Of course, in the case we are discussing there is no problem, since App Doc B has merely copied what the document says in elation to the matter concerned- but life is not always as simple as that.
In the case of electrical wiring, Part P of the Building Regs is just one sentence, which essentially requires work to be done safely. Approved Doc P is no better, in that it really talks only of the 'bureaucracy', not of anything electrical. It suggests, but does not attempt to 'require' (again, it couldn't), compliance with the Wiring Regs (BS7671). In this case, we have the added complication of a third document, the "On-Site Guide". This claims to be guidance on the application of BS7671, but it quite offer differs from BS7671 in terms of detail and states all sorts of things which some people (incorrectly) interpret as 'requirements', which do not exist in BS7671!
Kind Regards, John
Yes, BS is just recommendations and the Building regs are the law. If broken you can be in prison. Where confusion arises is where the building regs points to a BS, then that is law.
There is confusion all around. GaSafe on their web site said it is illegal for a GasSafe operator to pass an installation fitted by a non-GasSafe person. This is total tripe. No such law exists. Many boiler and CH systems are fitted by non-GasSafe plumbers on sites with a GasSafe man passing and commissioning. Until gas is run through the boiler is is not a gas appliance, just a lump of metal with water inside. But the Gas Safe men believe all this self interest organizations spout. The average tradesman has no time to trawl though the building regs. Most would not understand them in detail anyhow. So they believe what others tell them.
There is confusion all around. GaSafe on their web site said it is illegal for a GasSafe operator to pass an installation fitted by a non-GasSafe person. This is total tripe. No such law exists. Many boiler and CH systems are fitted by non-GasSafe plumbers on sites with a GasSafe man passing and commissioning. Until gas is run through the boiler is is not a gas appliance, just a lump of metal with water inside. But the Gas Safe men believe all this self interest organizations spout. The average tradesman has no time to trawl though the building regs. Most would not understand them in detail anyhow. So they believe what others tell them.
Last edited:
Indeed - but, as I implied, it gets more complicated than that in terms of electrical wiring. Approved Doc P (which is the only document that what id actually required to satisfy the one-sentence bit of law) indicates that compliance with the Wiring Regulations (aka BS7671) is one way of satisfying Part P of the Building Regs, but that it is not the only way, so that, in law, complaince with BS7671 is not actually 'required'.
In practice, it would undoubtedly be an uphill struggle to try to convince a Court that one had complied with the law (Part P of Building Regs) even though one had not fully complied with BS7671, but it is theoretically possible that one could.
Kind Regards, John
So anyone who does the work safely in the installation, that means safe when working, and the finished end product, can do it.
Yet many organisations insist on an electrician who is a member of one of the electrical organisations do the work, or pass it off. This is not necessary by law.
In law, yes. The entirety of 'the law' (Part P of Building Regulations is:
Indeed. However, since the law is so vague, one cannot blame organisations, or individuals, for trying to obtain some reassurance that people undertaking electrical work for them are competent so to do. Whether membership of one of the electrical trade organisations necessarily guarantees that is perhaps a matter for debate.
Kind Regards, John
Would you rather that (for example) local councils used taxpayers' money to obtain and verify the qualifications of people when deciding whether or not to accept the certificates they issue?
DIYnot Local
Staff member
If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Are you a trade or supplier? You can create your listing free at DIYnot Local
Sponsored Links
