Electricity to shed/outbuilding

[futureboy]

Hi All

I'm having a concrete shed installed in my garden and i'm going to turn it into a workshop/office.

Does anyone have any tips on:
-how to insulate it
-best method of heating it (e.g. electric heater)
-how to get electricity in there (lighting, sockets etcs) and if anyone knows the costs involved.

Any info would be appreciated.

Thanks

 

[Axel]

Insulate it with insulation...! You can get that plasterboard stuff with hard foam attached, or use fibreglass type insulation, like the stuff in lofts. It will make the shed smaller, of course, because you'll need to put the insulation on the inside.

To heat it, electric heater probably the easiest, unless you're in there all day, in which case you could run insulated pipes from your house central heating, if it was quite close.

To get power to the shed you are supposed to use armoured cable, 2.5mm square conductors if you want to use a heater in there, and it has to be very well installed with the correct cable glands to make a safe, waterproof connection. Also, this outside circuit MUST be protected by an RCD, which should be located inside your house, preferable at the consumer unit.

Maybe you might consider a secondary 1.5mm cable run to switch the light on in the shed from the house, otherwise you might want a remote control...

 

[industryspark]

axel wrote

To get power to the shed you are supposed to use armoured cable, 2.5mm square conductors if you want to use a heater in there, and it has to be very well installed with the correct cable glands to make a safe, waterproof connection. Also, this outside circuit MUST be protected by an RCD, which should be located inside your house, preferable at the consumer unit.

Maybe you might consider a secondary 1.5mm cable run to switch the light on in the shed from the house, otherwise you might want a remote control...

No offence but most of this is a load of carp. 2.5mm sized cable might be suitable, then again it might not-there are many more factors to consider before you can confidently state a cable size.

You do NOT necessarilly need rcd protection on the cable to the shed, again, other factors may dictate this but its more likelly that you wont require rcd protection to this circuit.

Best advice is to get qoutes from 3 recommended sparks and see which you feel happiest with.

Regards.

 

[Axel]

Practical and reasonable common sense advice is to use 2.5 cable - unlikely to need more power unless there is a kiln or a cooker in the shed. And why fit a narrower cable?

Extremely advisable to have RCD protection on any outdoor circuit. Maybe you are being the devil's advocate, but in a garden shed you are more likely to have water / damp related issues and it is irresponsible to advise against RCD protection on any outdoor circuit.

 

[spark1]

Industryspark is giving good advice here Axel.

There are many factors to be taken into consideration on this proposed supply.

If it is intended to utilize the earthing system from the main house then
.it is quite possible a 3-core 10mm cable will be required.
Industryspark was stating the cable does not require RCD protection which is correct. The circuits inside the Shed / office / workshop of course will require 30ma protection.

Futureboy when you obtain quotes ensure you are going to receive an Electrical Installation Certificate AND a Building Notice Compliance Certificate
off the sucessful Tender

 

[ColJack]

we don't do common sene advice on here, we do proper and correct advice..
the correct advice is that the cable size would be determined from the anticipated load and the length of run, coupled with de-rating factors for things like fuses, installation method and so on.

 

[industryspark]

Axel wrote

Practical and reasonable common sense advice is to use 2.5 cable - unlikely to need more power unless there is a kiln or a cooker in the shed. And why fit a narrower cable?

I never said 2.5 wouldnt be suitable, neither did i suggest fitting a 'narrower' cable. What you have to consider though is other factors such as load, volt drop, diversity, earth fault loop impedance.

If you read the original post the poster says a 'concrete shed' which is going to be used as an 'office/workshop'.

Not exactly sounding like your average garden shed to me. Now, without knowing what load is going to be pulled and applying some diversity and design, it is silly to suggest 2.5 off the top of one's head imo.

Extremely advisable to have RCD protection on any outdoor circuit. Maybe you are being the devil's advocate, but in a garden shed you are more likely to have water / damp related issues and it is irresponsible to advise against RCD protection on any outdoor circuit.

Why is it advisable to have an rcd on this 'submain' circuit or 'any outdoor circuit'? Please sight the regulation in the 17th edition that you think requires this.

Im not being devils advocate, just considering good design practice. What is wrong with having mcb at the house end and rcd'ing circuits within the shed CU? I can give you some benefits of this if you so like.

Regards

 

[futureboy]

Thank you all for your comments and suggestions. I will definitely get a few quotes from electricians and unsure that they are able to supply the correct paperwork, certificates etc.

Cheers all!