DIY Doctor UK DIY Forums

I want to install in my workshop:

4 x IP65 T8 36W twin 48" lights
2 x IP66 13A 2G DP switched double sockets
2 x IP55 10A 1P Push-Button light switches
25mm white PVC conduit tubing throughout

The consumer unit is upstairs, directly above the right corner.
I want to install as much as I can before I get an electrician to check it and wire it into the consumer unit.
I'm confident with my DIY skills, but always extra cautious with electrics.
Can someone tell me what gauge wire I'll need for the lights & switches, as well as which junction/distribution boxes I should fit?
As I said, it will be checked and finally wired by a certified electrician to sign it off.

Why do you want conduit? The twin and earth cable will not fit easy through conduit. You would need to use singles.

For lighting 1 or 1.5 mm sq and for sockets 2.5 mm sq but it would mean a lot of work.

There are many options and it is down to risk assessment when selecting cables. Best cable for workshop is mineral insulated but this is not a cable for DIY work. So second best is Ali-tube which can still be made to look neat you will find it used with fire alarms a lot.

Plastic conduit does not really protect cable any better than the sheaf on standard twin and earth if mechanical protection is required then steel conduit is the way to go.

I have used both SY and SWA in workshops but the selection is down to personally preference and doing a risk assessment. Most workshops don't required special measures to protect the cable. Since I have no idea what will go on in the workshop can't really advise on cable selection.

ericmark wrote:Why do you want conduit? The twin and earth cable will not fit easy through conduit. You would need to use singles.

I have used both SY and SWA in workshops but the selection is down to personally preference and doing a risk assessment. Most workshops don't required special measures to protect the cable. Since I have no idea what will go on in the workshop can't really advise on cable selection.

Thanks for your reply.
The idea of the conduit was just to keep everything tidy.
I'm only going to be using hand power tools & chargers. It's only a hobby workshop repairing motorcycles in my spare time.
I need to do as much of the prep' work as possible to keep the costs down, before I get a sparks to check it and wire it in to the CU.

First question is the legal bit and to be frank I personally don’t care, but I should point out in England rest of UK is different new circuits need notifying to LABC which is often a silly price.

I will assume you are going to do it correct if so then get one light and one socket put in by a scheme member electrician then extend on his work. The electrician can’t sign off your work.

There is nothing to stop you surface mounting cables, but for neatness trunking is far better than conduit. With trunking if you use the sticky back stuff after it has been fitted go around it with corking or silicon sealant the sticky back always seems to fall off in time but as the stick back starts to release it’s grip so the corking or silicon sealant sets and takes over plus makes the whole job look better.

You can get twin and earth in trunking far easier than in conduit although no need to use twin and earth can use flex if you want flex will go down conduit easier than twin and earth.

No real need for IP65 standard fittings will do. For a workshop the idea is to avoid strobe effect the twin fitting one with capacitor and one without was an attempt to do this. However today we would just use HF fittings if worried not sure on LED fittings they may also stop the effect and since the LED tube is plastic not glass it also gets around the breaking a tube problem.

HF works out more to install than LED, but HF costs less to renew tubes latter. Not convinced that LED is better both HF and LED have about same output per watt and tube life, but LED tubes tend to have a lower lumen output than fluorescent and since I expect it’s the spread of light your after rather than being super bright 4 x 1200mm (4 foot) 18W tubes at £15 each approx 18W each should be more than ample for the space. That’s 4 x 1800 lumen 7200 lumen is a lot of light. My living room has 2300 lumen so 4 tubes would be three times brighter.

I would go for outside switches as they are big and you can switch them with your elbows so not getting grease all over them and if you did the switch plate could be removed and put in the dish washer.