Running Cat6 with power cable?

[Sponge]

My house is being rewired this week. At the same time I am running cat6 to 3 bedrooms and 2 reception rooms. All from an under-stairs cabinet.

My electrician was asking me how/where I was going to run my cables and he suggested I just run them next to his power cables; saves me having to chase more channels.

I said I was worried about interfence, etc, and he said not to.

So, is running network cable next to power cable a 100% no-no? Or is it just not recommended? Will it make any difference? If so, will it actually be discernable in a domestic environment?

I'm spending a few hundred quid doing this and now is the time to get it right; but, is the time, effort, mess and expense of running in separate channels, cutting floor boards, drilling holes in joists* and making good afterwards worth it? At the end of the day, I guess only I can decide that, but I'm still asking here.

* Downstairs is ok - there is a void just big enough to crawl into and route cables. However, upstairs is an issue and will require crossing many joists.

Edit: I may as well ask while I'm here - what are the guidelines for cutting into joists?

The DIYnot 'How To' simply states:

The joists will have to be drilled approximately 50mm (2 inches) from the top, large enough for the cable to be able to get through. When the holes have been drilled, threadle through the length of cable.

But I need to route 4 x cat6 in one direction and 8 x cat6 in another, so I'm concerned they won't fit in any holes that meet spec.

 

[mattylad]

As its before you have done it, run 2 cables per room.

So many things want net access these days a single point is not enough, running 2 will save needing a switch etc in the rooms.

 

[foxhole]

Cat 6 should not be run next to power cables and should not even cross it without a suitable gap.

 

[Monkeh]

The cables should be separated for insulation purposes, but electrical noise is not a serious concern. Stay 50mm away, you can follow the same route. If you must cross, insert an insulating material between the cables (PVC oval capping suffices).

 

[Sponge]

As its before you have done it, run 2 cables per room.

So many things want net access these days a single point is not enough, running 2 will save needing a switch etc in the rooms.

I'm running 4.

My rewire 1st fix is done and I'm yet to start laying the network. I'm trying to find a route that'll keep away from the power and minimise damage to walls. It's proving difficult. But if I'm going to rip the place apart, now is the time to do it.

 

[Sponge]

I've been lifting floor boards that the electricians used and a few new ones of my own. I've noticed something a little worrying.

On one full run of the house, front to back (joists go left-right), they've drill holes right underneath notches. They didn't make the notches; they appear to have been there a while. I don't know what they've been used for. They've also drilled two holes, right next to each other. All of which appears to not meet requirements listed here.

Adjacent holes must be at least twice their diameter apart and no hole may be within 100mm (4”) of a notch.

I'm able to use the notches to run much of my network cable. They're just big enough to take 4 Cat6 cables. But the extent to which the joists are cut is now a worry.

 

[seasickstevie]

Don't like the sound of those notches and holes

Having said that, lifting boards after the heating guys have been, you see that sort of thing all the time.

As a matter of interest, why do you need four CAT6s per room?

Just noticed how old this thread is.

 

[Sam Gangee]

My electrician was asking me how/where I was going to run my cables and he suggested I just run them next to his power cables; saves me having to chase more channels.

Your electrician should read: "Requirements for Electrical Installations - IEE Wiring Regulations 17th Edition, Part 5."
Section 528 Proximity of Wiring Systems to Other Services:

Basically, don't do it. Apart from the risk of interference from "spikes" on the mains supply (e.g. neighbour using an arc welder) there's a potential safety problem.

This might also be of interest:
http://www.esc.org.uk/fileadmin/user_upload/documents/industry/best_practice/BPG5_08.pdf