Best options to extend BB to garden office?


I've had a garden office built which I'm now having fitted out with power and so on.

As part of that, I'm having a trench dug for an armoured cable to the room from the mains power distribution board in the garage, which is around 40/50 metres away.

The electricians are going to supply and fit all the power elements (grounding spike, fuse board, trunking in the office etc) but asked if I wanted to lay a network cable at the same time - presumably an RJ45 or similar.

My question is am I better off trying to support a wired extension to a small switch or wireless access point in the garden room or try to extend WiFi to the garden via directed or unidirectional antennas/extenders?

If I got the wired route then I need to connect the network cable they lay to <something> at either end - my router is on the first floor next to the main BT socket so need to bridge that gap firstly.

I already use powerline adaptors to a small powered switch on the groundfloor which supports my xbox/tv etc in the living room.

Usage in the garden room will be for xbox/tv/internet access. Ideally I don't want to spend a huge amount if I can avoid unnecessary expense - its for light home use not corporate grade!

Thanks in advance.


Distinguished Member
Ask your sparks to run a separate 25mm plastic conduit (with welded joints), from house to garden room, with at least 6" separation from your armoured cable, in the same trench. Once laid, you can suck a puller string through, using a vacuum cleaner and polythene bag. Use the string to draw a puller wire, which can then be used to draw some cat6 (lubricated with washing up liquid). Ask the sparks to try and avoid too many right angle bends if possible (makes pulling easier). It will be far cheaper than a wifi link (especially if you have a trench in place) and will allow you to pull multiple cables if necessary, or replace them if they fail. The trench should initially be backfilled with sand (beneath and above the conduit to protect it) and a layer of tracer tape / mesh before backfilling with soil.
At the house you may need to work a cable route from your router to the garage. In the garden room, terminate with a punch down block and connect to a small switch via a patch cable. You maybe able to plug a cheap access point into the switch to provide local wifi if necessary.


Active Member
Wired wired wired wherever and whenever you can.
I have done the same and ran 4 cat6 (although cat5e would do the job) in a 25mm conduit from the 24 port switch in the house to the office. Two are hooked up to PCs, 1 is used for the phone and the 4th to a TV. I have since found out there is conduit grade Cat x cable but mine 4 years on works fine


Distinguished Member
Duct grade Cat6 is expensive and hard to bend or terminate. Running in a sealed conduit allows you to re-draw a new cable if it (or they) fail. I totally agree with @rs6mra. I have had Cat5e in the ground for 10 years and its still running (although becoming a little brittle now).

PS Draw a pair of cables, rather than one. A spare is invaluable.
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Distinguished Member
Agreed, go wired! Ordinary Cat 6 will survive quite well in conduit - mine has been in 16 years now and is still going strong. Put in a pull chord so you can replace it just in case.

One thing that concerned me was your sparkies putting in a ground spike. Unless your house already has local earth electrodes and a TT supply, you probably don't want or need the spike - and it could be a safety / fire issue in the event of a fault. Without getting into the technicalities, in newer properties your earth is probably derived from the neutral supply to your house. If you add another ground into the earth path, in the event of a neutral fault elsewhere in the system, all the power for your street could end up going along your supply cable and to your new earth. That would be a bad thing and the current could melt things and cause a fire. Older houses have a seperate earth connection back to the sub station, but the danger remains if that earth was to fail, as your new earth spike would again become the earth for everything after the fault.

Your sparkies will need to check with the supply company what type of supply you have. You would only need or want an earthing spike if you have a TT supply. More info here: Earthing Types - DIYWiki


Thanks for all the answers/responses. I'll be having a chat with the sparks and get some pricing.

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