Shed Electrics

[ShedWise]

Hi folks,

Just to clarify, I'm not intending on doing any electrical work myself.

However, I do want to do as much work as possible, so all I need is a sparky to connect the wiring up to what I want.

Basically, I want twin sockets on each wall, and also lighting. My shed is wooden, and I intend on insulating it first.

I want to know, is it acceptable to building regulations to run the wiring inside some form of trunking, so I can insulate without worry - I hope to use Kingspan or similar, but it may not be plausible. If so, any suggestions as to what sort of trunking is best?

Thanks all

 

[big-all]

on the insulation front you need outer skin 1" air gap breathable membrane insulation and inner wall[ply or sterling board/osb

with the electrics you will have to find an electrician who will let you do the donkey work and pass the work before you start

 

[ShedWise]

Hi,

Thanks for your reply. I'm not after doing the cabling work, but wouldn't mind running trunking to show where I want it going, if you understand what I mean.

As for the insulation, does it have to be a 1" air gap? I was looking to use 25mn thick Kingspan boards, and then line it with some sort of board. I don't think the 'cavity' is 2" deep.

 

[big-all]

as the electrics are outside they come under part"P" so you need to notify the local building control before commencement for them to certify at your cost or for a registered part p electrician to self certify but both avenues require you to consult before you do anything

with insulation you may get away with say 12mm but would be happier with more i assume your talking 38 ish mm

 

[Zebra579]

The answer to this question may not be a simple one. The wiring regs contain a number of different "reference methods" which describe ways in which cable can be installed, whether in trunking, clipped direct, behind insulation etc, and each of these has a different impact on the size of cable which you can use and the load which it can carry. Other factors which impact on the cable size and the load which it can carry are the type of fuse or circuit breaker, ambient temperature etc etc.
It's down the the spark who will be giving you your certificate to design the installation if you want them to sign it off.
Having said that, the hard and fast rule is that cable mustn't be totally surrounded by thermal insulation but must have thermal insulation on one side only. If you don't want the cable surface mounted then they would probably be run ideally in a service void between your insulation and your plasterboard. In which case they don't need to be in trunking at all.

 

[ShedWise]

Thanks for the replies.

Are we on 18th edition now? I wouldn't mind having a look so I have an idea. If worst comes to worst, I'll see whether its acceptable to run cable on the inside boarding, rather than in the shed cavity.

 

[Zebra579]

No, 17th still but with 2011 amendments.

 

[ShedWise]

Cheers

 

[ShedWise]

Out of interest, is this stuff acceptable to line the inside of the exterior wall, roof, floor with?

http://bit.ly/13Jp7Mh

The shed floor is timber 'beams', if you will, and I have put some ply sheet over the beams, so would be putting it inbetween the two. I intend to put carpet down eventually.