Major Rewire of My New Flat

[davas]

Hello All,

Firstly a bit of background.. I've just bought a two bedroom ground floor flat. Amongst various work required to bring it up to standard it requires a major electrical rewire. There are only 10 sockets in total throughout the entire property and all lighting wires are ran through trunking (looks very crap!).

I haven't made a decision yet as to if i get a part p registered person in to do the work or i go down the notify LABC route/hassle (but that's a completely different thread!). So whichever route i decide on I would like to spec out the work with you fellas first (either to do the job or know exactly what any sparky's are trying to install)...

Circuits:
1 ring main (2.5mm) 12 Double sockets
1 kitchen (2.5mm) 6 Double sockets
1 cooker (10mm) 45A Switch and 45A Outlet
1 central heating combi (2.5mm) 20A DP switch
1 electric shower (10mm)
1 lighting (1.5mm)
all twin and earth BS6004

Currently there is an old Wylex CU with wire fuses etc and four circuits. Looks ancient to me!

I've seen this on screwfix direct. From what i've read it seems to fit the bill. I'll need to buy extra MCB though i know.

9 way split load consumer unit
-100A DP Main switch
-80A 30mA RCD
-5 x MCBs (1x40A,2x32A,1x16A,1x6A)

Which circuits would you put on Which rating MCBs?

Another major problem i found was that there appears to be no earth connection to the house either from the supply or from an earth rod etc. I would therefore install a new earth rod. Would this have any bearing on the CU selection or any ratings given the fact i'd have a TT setup?

Also it's worth pointing out that the property has a new electrical meter (installed late 2004).

(Pictures are available on request for any aspect of the circuits should i be speaking rubbish and you need some clarification)

It would be massively appreciated if you could make any comments on the above (Part P aside at this point in time)

Thanks and a Merry Christmas

Chris

 

[Big_Spark]

Davos..if you have a combi boiler, you obviously have gas..so why not get a gas cooker and a Combi complient shower...

You save the cost of installing the larger circuits for a start, you save energy costs on running the appliances, gas is better to cook with, and Combi powered showers are far more efficient and better than electric poo ones..

 

[JohnD]

on the cooker front... he'll want to sell the flat one day, some people like to cook electric... easier to put in the circuit now than later.

It's always worth (I think) putting in a bigger CU than you think you need, costs very little extra for the fresh air and plastic that you aren't using, may turn out to be handy later.

"Which circuits would you put on Which rating MCBs? " is an odd q to ask. Obviously 32A for the 2 rings, 6 for the lights, if you want a 45A cooker then obviously 40A MCB isn't enough;but would do for the shower; 16A for the immersion heater you've forgotten to mention.

It's unusual not to have an earthing point, does the building have an overhead supply?



and... just because you've seen a bargain CU at Screwfix doesn't mean it's the right one for you, especially if you have an overhead supply.

 

[andy]

are you sure you have a TT supply? it does make a big difference and youll need to know what you need before ordering any CU

 

[davas]

"Which circuits would you put on Which rating MCBs? " is an odd q to ask. Obviously 32A for the 2 rings, 6 for the lights, if you want a 45A cooker then obviously 40A MCB isn't enough;but would do for the shower; 16A for the immersion heater you've forgotten to mention.

and... just because you've seen a bargain CU at Screwfix doesn't mean it's the right one for you, especially if you have an overhead supply.

Thanks JohnD...

I know it was an odd question but was mainly just about the combi boiler. Which rating should that be on do you think?

Also there isn't an immersion heater, (there was one in the past which was never decommissioned when the combi was installed)

I only posted the screwfix CU as an example of a so called "standard" CU to see if that would be up to the job.

I'm not entirely sure about the overhead supply... my electrician friend said i definitely needed an earth rod installing though.

 

[davas]

are you sure you have a TT supply? it does make a big difference and youll need to know what you need before ordering any CU

I don't think I have an earth from the supply AT ALL presently. There is one connected to the mains gas pipe though.

 

[davas]

Davos..if you have a combi boiler, you obviously have gas..so why not get a gas cooker and a Combi complient shower...

You save the cost of installing the larger circuits for a start, you save energy costs on running the appliances, gas is better to cook with, and Combi powered showers are far more efficient and better than electric poo ones..

I'm not sure about the cooker yet (maybe a gas hob and electric oven)but i definitely want an electric shower (just my personal taste). Also getting corgi plumbers in to extend gas pipes etc will cost more than have a sparky put in a new circuit when they are already 'on the job' so to speak.

 

[andy]

I know it was an odd question but was mainly just about the combi boiler. Which rating should that be on do you think?

I only posted the screwfix CU as an example of a so called "standard" CU to see if that would be up to the job.

I'm not entirely sure about the overhead supply... my electrician friend said i definitely needed an earth rod installing though.

1: 6A radial, 1.5mm²

2: no such thing as 'standard'

3: your not sure if you have an overhead supply?

 

[dingbat]

Chris, I think the very first thing you should be sorting out is that earth. If you are sure there is no earth connection, contact your District Network Operator ( http://www.energynetworks.org ) and report it as a fault. Get this sorted out as a priority

As has been mentioned previously, if you do have a TT supply, this will affect the CU you install. If this really is the case, then just banging in an earth rod is not as straightforward as you might think. How will you measure its effectiveness?

And there may be a reason your current wiring is installed in trunking - depending on the construction and the cooperation of neighbours (above, in your case) flats can be a real nightmare to rewire.

 

[JohnD]

OK, I understand about the immersion heater now - combi = no hot water cylinder = nowhere to put an immersion. On the days when your combi breaks down you'll just have to wash with a kettle

 

[davas]

OK, I understand about the immersion heater now - combi = no hot water cylinder = nowhere to put an immersion. On the days when your combi breaks down you'll just have to wash with a kettle

I'll go to my mum's house!

 

[davas]

Chris, I think the very first thing you should be sorting out is that earth. If you are sure there is no earth connection, contact your District Network Operator ( http://www.energynetworks.org ) and report it as a fault. Get this sorted out as a priority

As has been mentioned previously, if you do have a TT supply, this will affect the CU you install. If this really is the case, then just banging in an earth rod is not as straightforward as you might think. How will you measure its effectiveness?

And there may be a reason your current wiring is installed in trunking - depending on the construction and the cooperation of neighbours (above, in your case) flats can be a real nightmare to rewire.

I read that the network operator would treat the earth as a consumer issue if they don't provide an earth on the mains supply... will look into it as a priority though as you suggest!

Current wiring is in trunking but chasing the new wiring will not be a problem as the whole flat is to be replastered once wiring is complete. So i can make nice big holes in the ceiling etc!

 

[JohnD]

I read that the network operator would treat the earth as a consumer issue if they don't provide an earth on the mains supply... will look into it as a priority though as you suggest!

If your flat is in a country area, you should easily be able to see if the electricity supply comes in on poles through the fields. Otherwise, it's extremely peculiar for you not to have an earthing point and for the electricity supplier not to provide one.

 

[davas]

I'll post a picture as soon as i get some webspace to host it on to clear up the earth matter.

Merry Christmas everyone!

Thanks all for your replies so far![/img]

 

[breezer]

I'll post a picture as soon as i get some webspace to host it on to clear up the earth matter.

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