Wetroom requirements and 12v extractor costs

My understanding now is that if Z1 an IP rated fan could be used as the CU is modern and has an RCD?
The RCD requirement now is for all new circuits to a bath/shower room and nothing to do with whatever appliance is involved.
IPX4 (or better) fans are allowed in zone 1.

Both IP rated and SELV 12V fans come at a fraction of the figure the electrician is asking for his fan...
Similarly the price has nothing to do with whether 12V or 240V.
 
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It's IP24.
Do you have the same problem as me in understanding how IP24 can exist?

In other words, can you see how an enclosure with holes of at least 2.5 mm diameter (otherwise it would be at least IP34) can be able to resist ingress of water from an unshielded spray nozzle, from any direction, for 5 mins?

Kind Regards, John
 
I did think about that and thought it must be better than IPX4,

but no, I havent figured it out yet - unless they mean you just cant get your hand/finger? in anywhere and the electrics are '4'.
Not exactly correct, though.

So, what does IPX4 mean? Do the figures only relate to the electric parts?
 
The RCD requirement now is for all new circuits to a bath/shower room and nothing to do with whatever appliance is involved.
IPX4 (or better) fans are allowed in zone 1.


Similarly the price has nothing to do with whether 12V or 240V.

Perhaps I should try to make myself more clear. On one side we have requirements and on the other costs.

I understand the above and since the CU has two RCDs then my circuit already complies with the RCD requirements?

https://www.sparksdirect.co.uk/blog/ip-rating-in-the-bathrooms-bathroom-ip-zoning/

The point of my thread is to understand if the electrician is making up his own requirements (12v SELV in Z1?)and further having no basis for the higher cost of the fan. Any reasonably priced unit with the right IP spec could fit the original budget...
 
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So, what does IPX4 mean? Do the figures only relate to the electric parts?
I think it all relates only to 'electrical parts' ....

Strictly speaking, IPX4 just means what it says - protection against water ingress as I described in my previous post, regardless of how 'bad' (low) the first figure ('solid particle protection') may be. However, as I implied, I really can't see how it could be IPX4 without being at least IP34 (and I would actually be more inclined to say at least IP44).

Maybe when manufacturers claim IP4X IPX4 it simply means that they haven't bothered to do the 'solid particle tests', even though I believe that, if done, those tests would inevitably show it to be at least IP34, quite probably IP44, or maybe even better?

Kind Regards, John
Edit: typo corrected
 
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The point of my thread is to understand if the electrician is making up his own requirements (12v SELV in Z1?)and further having no basis for the higher cost of the fan. Any reasonably priced unit with the right IP spec could fit the original budget...
We know you have RCD protection and, as you have been told, a 230V fan with adequate IP and said by manufacturer to be suitable for Zone 1 would be acceptable, as would any 12V fan. Only your electrician can tell you why he has suggested one which is more expensive than (for wither 230V or 12V) it necessarily needs to be.

Speaking personally, he sounds like an electrician that I would probably be wanting to replace.

Kind Regards, John
 
The point of my thread is to understand if the electrician is making up his own requirements
Regulations do not require a 12V fan. However they do not prohibit fitting one either.
Whether £100 for the fan is reasonable depends on which fan is being specified - there are plenty of fans both 12V and 230V which cost more than that, and plenty of others which are far less.
 
Speaking personally, he sounds like an electrician that I would probably be wanting to replace.

Kind Regards, John

He is coming from the builder's side, if it was me I'd have thrown him out half way through the project. Wiring interior ceiling lights and outdoor PIR /wall lights on one MCB speaks for itself...
 
He is coming from the builder's side, if it was me I'd have thrown him out half way through the project. Wiring interior ceiling lights and outdoor PIR /wall lights on one MCB speaks for itself...
Nothing wrong with that! Obviously in an ideal world you would have them separate but there’s a cost implication in that, and unfortunately these days a lot of jobs are very price driven.
 
£5 for an extra MCB makes all the difference....
 
£5 for an extra MCB makes all the difference....
Not just the MCB though is it? If there's a L+N at a rose or switch 5 metres away from your outsides lights you're going to cost it to go to there vs. the CU which could be many more metres away.
 
If/when the outdoor circuit trips for whatever reason or your need to kill the power to work on the outside light, your indoor kitchen lights go off too!

Now, how come I never thought of that, sounds like an amazingly cost saving decision.
 
Well, you don't need a separate circuit to be able to fit a 2P isolator for the outside lights, and that deals with those objections (apart from the inside lights being off until you isolate the outside if they are causing a trip).

But the most likely trip would be an earth leakage one, so even if you had 2 circuits you'd have to make sure they were on different RCDs, and unless you had an RCD dedicated to the outside lights, or were using RCBOs, they would be sharing an RCD with something.
 
And there's more testing.

Also, before too long extra MCBs mean a bigger CU

But...

And if I were to make my story simpler...

an electrician turns up at a house with a 15 way CU, he looks at the existing circuit and notices separate MCBs for "Front outside lights", "Garden Rear Lights", "Upstairs Lights", "Downstairs Lights".

The electrician decides the most suitable layout for the new extension will be all new lights on one MCB, but keeps it a secret until the day client needs to turn off the faulty PIR :eek:
 

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