Bathroom upgrade RCD

[oceanbassboy]

Hi all,

I am planning upgrades of two bathrooms and will be installing new down lights and extraction. I understand that these items will require RCD protection.

I have trolled a number of posts on here with a variety of advice. It would seem the easiest solution is to install an RCBO in place of the existing MCB on the Upstairs lights circuit at the CU.

Can anyone see a problem with this, or does each bathroom/installation need to protected individually?


Existing MCB is rated 5A with a max load of 800 watts... RCBO will be 6A with a max load of 1000 watts. will the existing cabling cope with the Amp upshift?

Thanks in advance for any advice.

 

[PrenticeBoyofDerry]

The existing cable should be be okay, assuming that it is 1.00mm or above.
RCBO's are a good option as a replacemnet for MCB's offering the added protection given by a RCD.
Providing the consumer unit does not already offer the circuit RCD protection.

It will mean that your are installing a new protective device, which may well be considered notifiable work under part p.

 

[ban-all-sheds]

I am planning upgrades of two bathrooms and will be installing new down lights.

What size?

In your application for Building Regulations approval, what will you say will be doing to ensure compliance with Part C, Part L and Part P?

 

[oceanbassboy]

Thanks for those replies. The CU doesn't have any RCD protection and I have sourced a RCBO to fit at £30ish. Just wanting to make sure that that was an acceptable solution and to avoid making illinformed decisions based purely on advice from contractors.

BAS not sure what you are referring to by "size", but as for notification and Regs compliance, I am in debt to many of the posts on this site alerting me to the process. As the work is bathroom and kitchen based and involves electrics, I assume it is all notifiable. However not one of the three contractors who have visited to estimate for the works mentioned building control or regulation compliance at all.

I have a meeting arranged with my extremely helpful LABC who when asked if the process might take Days/Weeks or Months was unable to commit in case I held him to it!

 

[ban-all-sheds]

BAS not sure what you are referring to by "size",

Diameter, really, what size bulbs do they take?

As the work is bathroom and kitchen based and involves electrics, I assume it is all notifiable.

Yup.

However not one of the three contractors who have visited to estimate for the works mentioned building control or regulation compliance at all.

Well, if they were all registered they might well not have done, because there would be nothing that you or they would have to do in advance, they would just notify afterwards through their scheme.

Whether or not they appreciate that they are supposed to be certifying compliance with all of the Building Regulations, i.e. including no moisture into the loft as per Part C, no heat-loss through insulation being cleared as per Part L, no inefficient lighting as per Part L etc, is another matter though...

 

[ericmark]

Existing MCB is rated 5A with a max load of 800 watts... RCBO will be 6A with a max load of 1000 watts. will the existing cabling cope with the Amp upshift?

Well 5A is 1150W and 6A is 1380W but very unlikely to cause any problems.

Building regulations is a problem as the LABC need informing as to if Part P is through them or if using self-certify system.

As BAS says not just Part P to comply with but also L for heat loss, and M for switch heights, J as well as F for fans if any fires are used in house.

I would want a written undertaking that the builder will be both complying with all building regulations and will be responsible for notifying the LABC. I have seen a number of jobs where the electrician only issued a installation certificate as the whole job he assumed was under building control and then the owner started to pester for Part P and only then did he realise it had not been included in notification.

His comments were the LABC had been on site and so he thought they were in charge of inspection for Completion Certificate. Which I suppose he had a point. So do get who is doing what in writing so there are no mistakes.

What I can't work out is why questions like yours are asked? I would assume an electrician is doing the work, so why not ask him?

Maybe I have this wrong but if your wanting to comply with regulations then the instruments required mean that unless a whole house rewire is being done then likely cheaper to get an electrician to do the work. And if your not going to follow regulations for inspection and testing then why worry about the rest?

Like the uninsured and unlicensed driver keeping to speed limits I suppose! but hopefully he will still get caught!

 

[oceanbassboy]

Thanks BAS

what size bulbs do they take?

I haven't spec'd the lamps yet. still undecided on ELV or 240V - plenty of threads to read through yet as there is a lot of divided opinion. There will be 3 lamps in each room max 50watt at the mo.

Thanks Ericmark

Well 5A is 1150W and 6A is 1380W but very unlikely to cause any problems.

Those are indeed the theoretical max loads, I was refering to the actual max loads adding all the fittings on the actual circuit before and after the work.

What I can't work out is why questions like yours are asked? I would assume an electrician is doing the work, so why not ask him?

The question is asked because talking to the three contractors who have quoted, 1 suggested fitting indivicual RCD's in the attic for each bathroom £150 ea. and 1 advised upgrading the CU £500+ the other is yet to respond. I found this site and is seems to have a lot of good info and keen participants.

With all due respect to professionals on here, not all professionals are fully knowledgeable or able/inclined to work out the best/cheapest/most effective solution. I intend to use professionals for the skilled aspects of the job, just chipping in with some labouring myself, without access to word of mouth references, I have used Checkatrade and Rated People to source contractors.

Just trying to do the right thing and manage contractors appropriately armed with a reasonable level of info. Also want to avoid getting ripped off... exactly what this site and forum are for. No?

Thanks for the pointers

The building control aspects of this thread are in train. I have requested confirmations form all quoting contractors and arranged a meeting with the LABC. If the forum is interested I will keep you posted.

 

[electronicsuk]

Can anyone see a problem with this, or does each bathroom/installation need to protected individually?

No, there's no need for individual RCD/RCBO protection for each bathroom, and changing the existing MCB out for an RCBO sounds like the best solution for you.

That alone doesn't necessarily mean you can avoid supplementary bonding in the bathrooms, although as you are only upgrading the lighting in these rooms, it's possible bonding may already be present from the original installation.

 

[ban-all-sheds]

I haven't spec'd the lamps yet. still undecided on ELV or 240V - plenty of threads to read through yet as there is a lot of divided opinion. There will be 3 lamps in each room max 50watt at the mo.

Sounds like you're planning on installing those useless little 2" diameter jobbies.

I strongly suggest you abandon that plan and draw up a new one based around installing lights actually designed to light a room.

 

[oceanbassboy]

lights actually designed to light a room.

Are you suggesting that 3No. GU10's at 35W or 50W won't light the same space as an existing 100 watt bulb, which is in itself too much for the space?

 

[ban-all-sheds]

Yes, and the fact that you're planning on installing 105 - 150W when you say that 100W is too much shows that you know it.

 

[oceanbassboy]

Hi BAS

If I knew this stuff do you think I would be trolling these forums?

I currently have a T shaped en-suite with a 100w light that is very bright but leaves 2 dark corners. I want to distribute the light better. 3 downlighters seems to do the trick. I have read posts, some of them written by you, suggesting that they aren't bright enough. 35w and 50w seem to be standard??

I am here looking for advice, although this topic wasn't my original post, you brought it up. Any suggestion on the type of fitting that might be better suited?

Thanks in advance

 

[ban-all-sheds]

Well - how else is anyone supposed to interpret an intention to fit up to 50% more wattage than "an existing 100 watt bulb, which is in itself too much for the space"?

The problem with MR16 downlighters is not how "bright" they are, it's where the light goes when it comes out, and basically they are like torches, you get a narrow beam. They are not designed to light up the whole of a space, they are designed to light up something specific that you point them at.

You could put 500W lamps in, if you could get them, and it wouldn't help.

Just google for bathroom lighting, and look at flush or semi-flush fittings, there are all manner of shapes, sizes, styles and finishes to choose from.

 

[oceanbassboy]

Thanks BAS,

Those were the kind of fittings I was trying to avoid, mainly because I don't like the look of most of them. However I take your torch explanation on board and will have a rethink... to be fair, if you were to happen upon me in the shower you would be more than grateful for a dimly lit bathroom!!

Thanks for the advice. Being a stubborn taurean I may end up sticking to my original plan and cursing you whenever I can't find the soap!!

 

[ericmark]

As BAS has said the small spot lights do send out a spot of light great if your lighting a picture from a distance but not a room.

The old 2D units light rooms very well with a lot less watts.

As to RCD's the box costs so better if all together also better if easy to access loft seems daft.

Consumer units have advanced through time and old ones can only take fuse or MCB and as time went one then MCB only as the RCBO came out the space was increased and you could fit the extra length needed with RCBO so where the consumer unit will take RBCO's that's normally best option but not all will.

Although £500 for a new consumer unit seems a lot in some ways it could be best option if old one will not take RCBO's as it then adds protection else where as well.

But cost of changing a consumer unit is also in finding faults as normally something is faulty and then the electrician has to find out what. It may have not been plugged in when he did tests.

I realise many don't use electricians and DIY and then don't ask real question but try to hid the bits they don't want us to know so run the risk of getting wrong info as a result. And yes do let us know how it goes as electricians we don't see it from customers side.

Lighting is subject on it's own and white walls and ceiling will give more reflected light of course so in a show room the little 50W spots will look great. But most people don't have white walls and ceiling so light is not reflected so much reduced.

I always used the GU10 fitting as it would take the 11W florescent fitting but the ELV type would not. However I see the standard BA22d bulb now have 12V florescent replacements so maybe the spot lights will follow. There seems to be new stuff out all the time. The LED lamps were like Toc H candles but they are improving. Consider the 50W stop has limited life so what will you fit once these are withdrawn like the peal light bulb was.

At design stage for a room you have more options but I was disappointed when I went for new fittings to find 90% and nearly all the cheap ones were tungsten and I had to really shop around to find fittings to work with discharge lighting. Guess shops are trying to get rid of stock before it becomes obsolete?

Can you get florescent soap!