Ducting for services for shed

[garyo]

Hi,

I'm just setting out the footings for my new extension. 6 feet away is a shed that I envisage will need power and maybe a network cable in a couple of years.

I'd like to lay an underground duct now to make things easier and neater in future (outside will be rendered) , and then when I'm having the extension electrics first fixed I can ask the electrician to push through some SWA for future use before everything gets plastered over.

My questions:

- How large should I make the duct? 40mm waste pipe, or 75mm guttering down pipe?

- What level should I pass it through the wall? I'll have 6 courses of brick between DPC and the top of the trench fill

- Where's best to bring it up? I guess it needs to be far enough into the wall that SWA can come out of the duct behind skirting board, which feels like it would need to be notched into the blocks under the DPC?

Thanks as always

 

[garyo]

Double post

 

[endecotp]

Use separate ducts for power and network, maybe a foot apart, to avoid interference.
Have large radius bends (or no bends!) if you want to pull things through.

 

[23vc]

I looked into this years ago and remember being told there’s always a risk of whatever duct filling with water. I ended up running SWA (not in a duct), not sure of the best option for comms cable tho

 

[noseall]

...and leave a draw rope in the duct with grasping handles each end (bits of batten to tie the rope around).

 

[Tigercubrider]

On my work site they seem to use plastic drainage pipe- designed to be buried.
There's also the bendy stuff that companies use?

It's supposed to be buried at a depth and a plastic tape added above

 

[garyo]

I'm wondering if I should bother now. On the other side of the house we had a similar situation where the electrician fitted a FCU next to a double socket on the ring then drilled straight through the wall, fitted a plastic SWA termination box then dropped the SWA down the wall.

That was a brick wall though. With render it's not going to be possible to clip the SWA over the bell cast... Is it?

 

[Tigercubrider]

When we got a new phone system at work, years ago, they added external little stump ducts
Basically the pipe ducts terminated outside the building, 12" above ground. Then small chimney style plinths built surrounding the pipes, with a concrete coping stone on top.

Could you have scope for that?

 

[23vc]

With render it's not going to be possible to clip the SWA over the bell cast... Is it?

It should be but would be a wider radius bend and not dead tight to the wall at that point

 

[^woody^]

Why mess about with a duct?

Just drop some armoured cable in the ground and be done with it