Summerhouse / Workshop electrics

[jonowilliams]

Before I start Im not going to attempt to wire into the mains myself! I know how to wire a ring and lighting circuit but no way am I confident to play with the mains or risk the house!

Im intending to start building a summerhouse/workshop in the next month or so and wiring it for electric.

The summerhouse is going to be my escape at the end of the garden when her indoors gets on my case! I also would like to use it for entertainment. Electrics wise in the summerhouse it would have 2 ceiling lights, 9.5kw water heater and a ring consisting of maybe 4 double sockets to run a tv, stereo and what ever other crap I will end up plugged in!

The workshop part would have 4 double sockets and 1 ceiling light. Wattage is a hard one to guess as with power tools it could be a few hundred to a few thousand watts!

Now you have what I want to do I'll give you the questions!

I've read from other threads on various forums I'd be best putting a switchfuse from the mains supply this for example http://www.screwfix.com/p/wylex-100a-switchfuse-100a-cf/60830

Run some armoured cable from the house to the SH/WS thickness depending on the electricians calculations, and connect to a consumer unit like http://www.screwfix.com/p/wylex-11-way-fully-insulated-main-switch-consumer-unit/26208

How 'correct' is this?

Would these be the correct parts for the electrician if I was to purchase them for him?

The summerhouse /workshop will be approximately 50ft away from the house if that makes any difference?

Am I correct in thinking I can install all electrics in the SH/WS and then get them passed off by the electrician and he just hooks up the supply?

Attached is a photos of the house supply etc

Thanks

 

[jonowilliams]

Also doing it like this would they need an earth rod?

 

[EFLImpudence]

You really need to discuss it with your electrician.

There are a lot of variables which are not worth commenting on if they don't apply.


You could search for previous similar threads.

 

[flameport]

Would these be the correct parts for the electrician if I was to purchase them for him?

Possibly, however if someone else is installing, DO NOT buy parts in advance, as they are likely to be the wrong ones, not required, not liked by the installer etc.

The summerhouse /workshop will be approximately 50ft away from the house if that makes any difference?

Distance makes a big difference, as does the intended load.
Why do you want a 9.kW water heater in there - this will require substantial sized cable and could overload the existing supply.

Am I correct in thinking I can install all electrics in the SH/WS and then get them passed off by the electrician and he just hooks up the supply?

No. If you want to install some/all of it, you must discuss this with the electrician before doing anything.
Installing things and then contacting someone later will not work - such as when the electrician arrives and discovers various problems, and then cannot 'hook it up' without substantial alterations to what you have already installed.

Whether earth rods, switchfuses, ring circuits and other items are needed or not is something you must discuss with the electrician.

 

[jonowilliams]

Would these be the correct parts for the electrician if I was to purchase them for him?

Possibly, however if someone else is installing, DO NOT buy parts in advance, as they are likely to be the wrong ones, not required, not liked by the installer etc.

The summerhouse /workshop will be approximately 50ft away from the house if that makes any difference?

Distance makes a big difference, as does the intended load.
Why do you want a 9.kW water heater in there - this will require substantial sized cable and could overload the existing supply.

Am I correct in thinking I can install all electrics in the SH/WS and then get them passed off by the electrician and he just hooks up the supply?

No. If you want to install some/all of it, you must discuss this with the electrician before doing anything.
Installing things and then contacting someone later will not work - such as when the electrician arrives and discovers various problems, and then cannot 'hook it up' without substantial alterations to what you have already installed.

Whether earth rods, switchfuses, ring circuits and other items are needed or not is something you must discuss with the electrician.

Thanks for the reply.

The water heater is simply is simply for that! Its the lowest watt Ive found for instant hot water supply rather than have a small tank... I intend to have a little bar area so dragging dirty mugs, glasses etc to and throw doesnt have much of an appeal to me.

I was thinking the electrician would probably put a henley block on the meter tails and supply the switchfuse from there to the CU in the SH?

 

[DaftPunk]

Do you own this property?

 

[ekmdgrf]

The water heater is simply is simply for that! Its the lowest watt Ive found for instant hot water supply rather than have a small tank... I intend to have a little bar area so dragging dirty mugs, glasses etc to and throw doesnt have much of an appeal to me.

Boil the kettle.

 

[Robin0577]

If you could manage with a little 3kw handwash unit like this instead of the 9.5kw water heater, you'd then be ok with a much more reasonable size of supply and cable. http://www.tlc-direct.co.uk/Products/TTT30slash3.html

It's quite likely that the main supply to you house isn't up to the job for that much additional load.

Edit - link wasn't working, fixed now

 

[PrenticeBoyofDerry]

There are small single point instantaneous water heaters that require a lot less than 9.5kW of power.

 

[jonowilliams]

If you could manage with a little 3kw handwash unit like this instead of the 9.5kw water heater, you'd then be ok with a much more reasonable size of supply and cable.

It's quite likely that the main supply to you house isn't up to the job for that much additional load.

Thought so! Wonder how a gas boiler from a caravan would fit lol

 

[jonowilliams]

There are small single point instantaneous water heaters that require a lot less than 9.5kW of power.

Not saw any myself? Do you mean the same as the fella above? One of them basin things ?

 

[PrenticeBoyofDerry]

There are ones that are above sink and below sink. Some vary in volume of litres held, some require safety devices such as expansion vessels and pressure relief valves or special taps that deal with the expansion, some don't
You can get them as low as 2kW.
For example http://www.rselectricalsupplies.co....-hf05vc_5784?gclid=CODRp5H3kr4CFYMIwwod5JQA9w
You have plenty of options, even a CSWC and 3kW cylinder could be an option.

 

[jonowilliams]

There are ones that are above sink and below sink. Some vary in volume of litres held, some require safety devices such as expansion vessels and pressure relief valves or special taps that deal with the expansion, some don't
You can get them as low as 2kW.
For example http://www.rselectricalsupplies.co....-hf05vc_5784?gclid=CODRp5H3kr4CFYMIwwod5JQA9w
You have plenty of options, even a CSWC and 3kW cylinder could be an option.

I think I will give the water heater a miss to avoid adding potentially a lot more £ to the project! I am now debting a caravan lpg water heater!

I'll find something!

 

[PrenticeBoyofDerry]

Without water heater, then 38A supply for sockets and lighting over 16m will require 6.0mm2 SWA. You could reduce the supply current for 20A socket circuit and 6A for lighting and use 4.0mm SWA but I would choose at least 6.00mm even be tempted to go for 10mm2, then you have scope to add a little if required at a latter date, but consideration for the demand already being used should be taken

 

[jonowilliams]

Without water heater, then 38A supply for sockets and lighting over 16m will require 6.0mm2 SWA. You could reduce the supply current for 20A socket circuit and 6A for lighting and use 4.0mm SWA but I would choose at least 6.00mm even be tempted to go for 10mm2, then you have scope to add a little if required at a latter date, but consideration for the demand already being used should be taken

I'd prefer 10mm2 just to be over cautious tbh. Best to be safe than sorry!

Might be a silly question but if I wanted external lighting would I be better to run a seperate circuit or would it be ok to be a part of the internal circuit too?