Power to the shed, my first electrical job.

[epsilonGreedy]

Getting the static caravan and shed plumbed and serviced has been a useful learning curve.

 

The newly installed garden shed (site workers laundry facility) now has a plumed in washing machine and tumble dryer. Power is provided using an extension lead and this needs to be replaced with fixed sockets plus a ceiling light all spurred off the static caravan's RCD proteced consumer unit.

 

What bits should I order if the starting point is a 3 core 2.5 mm2 cable that emerges through the shed floor in the corner? So far my shopping list is:

1. Double socket face plate.
2. Wall socket box (one designed to clamp on plasterboard after I have created a pseudo wall cavity with osb). 
3. Ceiling light (probably small led panel = no heat under wood roof).
4. Light switch (given possibility of wet hands I am thinking pull cord or proper exterior grade rubber light switch).
5. A local 1amp fusebox for the light circuit.
6. A junction box to branch out to the power and light circuits.
7. 20 amp twin and earth cable for the power circuit.
8. Lower amp cable for the light circuit.
9. Clips and maybe conduit.
10. Maybe waggo boxes to make the connecting up simpler.

 

 

[Jeremy Harris]

Sounds like it's notifiable work under Part P to me, so not a DIY job, I'm afraid.  Normally I'd be quite relaxed about stuff like this, but if this is going to be used by people working on your build then I think that your site insurers might need you to ensure that the work is installed, inspected and tested, with an IEC lodged on the part P register to cover it.

 

You might also want to think about whether it's reasonable to export the PE from your caravan connection to this outbuilding, or whether it would be better to TT the outbuilding installation.

[PeterW]

If its in a shed, then you would be better off using conduit and metalclad boxes for mechanical protection. As its a new circuit to a Consumer Unit then it is notifiable under Part P as per @JSHarris

[epsilonGreedy]

12 minutes ago, JSHarris said:

Sounds like it's notifiable work under Part P to me, so not a DIY job, I'm afraid.  Normally I'd be quite relaxed about stuff like this, but if this is going to be used by people working on your build then I think that your site insurers might need you to ensure that the work is installed, inspected and tested, with an IEC lodged on the part P register to cover it.

 

 

I plan to setup a proper independent external socket for the site e.g. power the mixer. The shed will be demolished within a year once the garage is built because the planning permission specifically forbids the erection of a garden shed. 

 

12 minutes ago, JSHarris said:

You might also want to think about whether it's reasonable to export the PE from your caravan connection to this outbuilding, or whether it would be better to TT the outbuilding installation.

 

 

The shed is butted up to the static caravan with just a small air gap between so not a separate outbuilding in terms of topology or cable routing.

Edited May 8, 2019 by epsilonGreedy

[Jeremy Harris]

Just now, epsilonGreedy said:

 

I plan to setup a proper independent external socket for the site e.g. power the mixer.

 

 

The shed is butted up to the static caravan with just a small air gap between so not a separate outbuilding in terms of topology or cable routing.

 

 

Even if the air gap is an inch it's still notifiable work under Part P, as it's a new external circuit.

 

 

 

 

[ProDave]

The caravan should already be on it's own TT earth. Use the same earth for the shed.

 

The site power socket should also be TT