"DavidD" wrote in message
. ..
I need to rewire some bits of my cellar. I want to use conduit so I can run
power, phone and lan.

I think I'll be able to squeeze it all into 20mm, the question is where to
get it, and the metal surface mount sockets?
I was thinking about screwfit but I have a feeing it might be a lot
cheaper elsewhere.

Any electrical wholesaler, although you might need to order metal conduit as
uPVC is more commonly used these days. However, if you think you can squeeze
it into 20mm conduit, you will probably find you can't. Earthed galvanised
steel trunking will providing shielding between power and signal cables, is
easier to lay cables into and is much easier when you want to make changes
later. You then only need to use conduit to connect individal outlets to the
trunking.

Also how does one join the conduit to the boxes? And what about junctions?

For steel conduit, you hire a threading machine from a hire shop and cut
screw threads on the tube. The powered ones require less effort, but the
manual ones are cheaper to hire.

Colin Bignell