Advice needed on wiring for a log cabin

[Valizzo]

Hi guys,

Me and my partner have recently decided to build a log cabin at the back of her mum's house.
The electrician that the company's working with, is planning on using a 316 swa as the main power cable, but I have concerns as the cabin will be used as a permanent dwelling for a while and we'll have to fit an electric shower.

Now I'm thinking, we'd need something that should be able to handle at least 20 kw power draw to be on the safe side.

I'm not an electrician but based on my limited knowledge we'd need something rated for at least 90 amps.
Please note the cable will be buried and around 25 - 30 meters in length.

I'm out of my depth here so advice and a second opinion would be greatly appreciated.
Also, they quoted us £720 for the wire itself which seems a bit steep?

Thank you!

 

[Andy78]

All in all it amounts to £3850 for everything including labour / switches / sockets / fuse board etc

I'll do it for £3.5k. I'll even chuck 25mm cable in to ease your mind

 

[ChrisElectrical88]

Trust their design, 16mm 63A submain its what i would imagine is going in.

 

[Valizzo]

I'll do it for £3.5k. I'll even chuck 25mm cable in to ease your mind

A most generous offer indeed!

 

[Valizzo]

Trust their design, 16mm 63A submain its what i would imagine is going in.

It's settled then, that's what I'll go with.
Thanks very much for your help Chris!

 

[ChrisElectrical88]

Just double check there not exporting PME in this situation and if bonding of the water submain is needed.

 

[Valizzo]

Just double check there not exporting PME in this situation and if bonding of the water submain is needed.

Just read about that thanks very much for the tip, I'll make sure to ask

 

[Midwest]

There's no trust in the world nowdays. Why not get several quotes, or just use a tradesperson recommended by word of mouth.

Not aimed directly @Valizzo, but this seems a common question being asked these days, on this forum. Not withstanding the forum is here to help, but one needs to do ones own groundwork sometimes (excuse the pun).

 

[Andy78]

There's no trust in the world nowdays. Why not get several quotes, or just use a tradesperson recommended by word of mouth.

Not aimed directly @Valizzo, but this seems a common question being asked these days, on this forum. Not withstanding the forum is here to help, but one needs to do ones own groundwork sometimes (excuse the pun).

I get the feeling this is an electrician provided by the cabin builders. I have had regular customers in this situation who have felt that they are unable to get quotes for part of the work as it is provided as a package.

 

[Strima]

I get the feeling this is an electrician provided by the cabin builders. I have had regular customers in this situation who have felt that they are unable to get quotes for part of the work as it is provided as a package.

My mother in law has recently had one built in her back garden, over £5k for power works. I've checked it over and the standard of work is crap. SWA not glanded, plastic conduit run externally but not correctly assembled allowing water ingress, the list goes on.

 

[davesparks]

Just double check there not exporting PME in this situation and if bonding of the water submain is needed.

With a 16mm 3 core SWA this shouldn't be a concern, the cpc is large enough bond any services

 

[Risteard]

16mm is fine as regards current capacity, volt drop could be a factor though. your cable cost should be no more than £200.

30 metres I would think nearer £260 to be fair.

 

[DefyG]

30 metres I would think nearer £260 to be fair.

Perhaps Telectrix is talking cost price with 1% margin? and/or excluding VAT!

 

[PhilGas]

No, that's just the price of the cable itself

As example, that cable from TLC Electrical Supplies would be around £150 for 20m!

 

[alasdairp]

No-one else has commented this, but just in case...
Permitted Development Rights usually allow small cabins up to 30 sq.metres and not more that 2.5 m high.

However, this is not the case if you want to have a residential log cabin which is going to function as sleeping accommodation or annex of your main house with water, drainage and electricity. If people will stay in it and it is not portable / moveable it will almost certainly (legally) need both Planning Permission and be inspected and tested to meet modern Building Regulations.

If it needs it and you don't get it, then if the LPA find out they may make you remove it completely.