Ok this is a bit hypothetical at present because we haven't bought the
building yet (and may never do if we can't find the owner).

We are thinking of restoring an old house and obviously I will be doing the
wiring myself and getting it inspected as there is no way that I will be
able to hide the fact that I'm doing it. I was thinking that as most of the
floors are likely to be ripped up I might run steel conduit around as is
done in commercial buildings and use individual wires for L, N and E as is
done in commercial buildings. Would this be ok? I presume I'd have to use
brown, blue and green/yellow wires.

--
Malc

Don't be humble. You're not that great.

"Malc" wrote
| We are thinking of restoring an old house and obviously I will be
| doing the wiring myself and getting it inspected as there is no
| way that I will be able to hide the fact that I'm doing it.

If you are worried about Part P then
(a) as long as you start the job this year, you are outside the scope of
Part P
(b) if it's a major job (any structural work, new drains, etc) you will be
getting Building Regs approval anyway, so just add the wiring on to the same
application.

| I was thinking that as most of the floors are likely to be ripped
| up I might run steel conduit around as is done in commercial
| buildings and use individual wires for L, N and E as is
| done in commercial buildings. Would this be ok? I presume I'd
| have to use brown, blue and green/yellow wires.

You can do this but -

(a) All conduit must be installed and complete before drawing wiring in.
This might not suit if you want to get some parts of the installation
finished and powered, albeit temporarily, before others.

(b) It is actually quite difficult to draw in wires into a partially
occupied conduit; the conduit must be sized sufficiently for the conductors,
and the conductors may have to have derating for grouping factor applied.
IOW, you have to plan which conductors will go in which pipe and show this
on your plans and calculations. It doesn't lend itself to as-you-go system
design.

You might look at plastic conduit and trunking systems. They're much nicer
to work with IMHO.

Owain

"Malc" wrote in message
. uk...
Ok this is a bit hypothetical at present because we haven't bought the
building yet (and may never do if we can't find the owner).

We are thinking of restoring an old house and obviously I will be doing
the
wiring myself and getting it inspected as there is no way that I will be
able to hide the fact that I'm doing it. I was thinking that as most of
the
floors are likely to be ripped up I might run steel conduit around as is
done in commercial buildings and use individual wires for L, N and E as is
done in commercial buildings. Would this be ok? I presume I'd have to use
brown, blue and green/yellow wires.


There is more to conduit wiring than just laying a length of 'pipe' for the
wires, you'll probably end up with many runs of conduit (this is why most
commercial buildings now use trunking) as cable size, heat built up and
radiuses etc. need to be considered when working out what can be contained
within each conduit run.

Unless there is a *very* [1] good reason to use conduit or you really want
to lay-out a load of conduit IMO you would be better off just using normal
T&E etc.

[1] such as needing to have cable runs in solid / inaccessible floors.

On Fri, 03 Dec 2004 21:59:27 GMT, "Malc"
strung together this:

I was thinking that as most of the
floors are likely to be ripped up I might run steel conduit around as is
done in commercial buildings and use individual wires for L, N and E as is
done in commercial buildings. Would this be ok? I presume I'd have to use
brown, blue and green/yellow wires.

Have you ever used steel coonduit before? It's not an easy option by
any means, I've done quite a bit of it on commercial and industrial
jobs and wouldn't dream of wiring my house with it.
Is there a particular reason why you can't use T&E?
--

SJW
A.C.S. Ltd
Please reply to group or use 'usenet' in email subject

In article ,
Malc wrote:
I was thinking that as most of the floors are likely to be ripped up I
might run steel conduit around as is done in commercial buildings and
use individual wires for L, N and E as is done in commercial buildings.
Would this be ok? I presume I'd have to use brown, blue and green/yellow
wires.

I'd say you've never worked with conduit? It's not easy, and *very* *very*
expensive. You'll also need a proper floor standing bender which also
doubles as a vice for threading it. Think several hundred pounds just for
that and the tools.

--
*Someday, we'll look back on this, laugh nervously and change the subject

Dave Plowman London SW
To e-mail, change noise into sound.

"Malc" wrote in message
. uk...
Ok this is a bit hypothetical at present because we haven't bought the
building yet (and may never do if we can't find the owner).

We are thinking of restoring an old house and obviously I will be doing
the
wiring myself and getting it inspected as there is no way that I will be
able to hide the fact that I'm doing it. I was thinking that as most of
the
floors are likely to be ripped up

Careful with that. If the 'old' house is listed you won't be able to tip
the floors up anyway. And if it is in a conservation area they still try to
encourage you not to do so.

Malc wrote:

Ok this is a bit hypothetical at present because we haven't bought the
building yet (and may never do if we can't find the owner).

We are thinking of restoring an old house and obviously I will be doing the
wiring myself and getting it inspected as there is no way that I will be
able to hide the fact that I'm doing it. I was thinking that as most of the
floors are likely to be ripped up I might run steel conduit around as is
done in commercial buildings and use individual wires for L, N and E as is
done in commercial buildings. Would this be ok? I presume I'd have to use
brown, blue and green/yellow wires.


You can, but its not necessary.

And its expensive.

Steel conduit is there to protect wires that would otherwise be exposed
- i.e. surface trunking.

Franly, its quicker and easier to lay T & E, and simply tie wrap it
loosely into bundles and hook the wraps over nails in joists etc.

Or use plastic trunking if you must.

--
Malc

Don't be humble. You're not that great.

":::Jerry::::" wrote in message
...
Unless there is a *very* [1] good reason to use conduit or you really want
to lay-out a load of conduit IMO you would be better off just using normal
T&E etc.

I would agree. No point using it generally.

[1] such as needing to have cable runs in solid / inaccessible floors.


I have often wondered about the benefit of running the T&E through conduit
in the walls to allow replacement of embedded cables without
replastering/redecoration. The fact the conduit is earthed (assuming it is
installed to Regs) would be an added safety feature too. The way the
regulations are going, I see the exception which allows cables to be buried
in walls at less than 50mm depth (Installation zones) being removed
eventually anyway, as people knocking in nails without checking for cables
must be one of the major causes of injury in decent installations
(relatively speaking).

Never actually done this though, as chasing out is bad enough as it is.

In article ,
"Coherers" writes:
":::Jerry::::" wrote in message
...
Unless there is a *very* [1] good reason to use conduit or you really want
to lay-out a load of conduit IMO you would be better off just using normal
T&E etc.

I would agree. No point using it generally.

[1] such as needing to have cable runs in solid / inaccessible floors.


I have often wondered about the benefit of running the T&E through conduit
in the walls to allow replacement of embedded cables without
replastering/redecoration.

You can normally pull replacement cables through oval conduit,
and although more difficult, often under capping too.

The fact the conduit is earthed (assuming it is
installed to Regs) would be an added safety feature too. The way the
regulations are going, I see the exception which allows cables to be buried
in walls at less than 50mm depth (Installation zones) being removed
eventually anyway, as people knocking in nails without checking for cables
must be one of the major causes of injury in decent installations

I've seen no figures to back up your conjecture.

--
Andrew Gabriel

"Andrew Gabriel" wrote in message
...
You can normally pull replacement cables through oval conduit,
and although more difficult, often under capping too.

Had a lot of fun trying it with steel capping once - no chance. Mind you,
that was mounted on uneven stone walls.


I've seen no figures to back up your conjecture.


Nor me, but I am sure we will see it when they want to change the rules
(especially spun for the occasion of course)

However, I have heard of people getting electric shocks from hitting buried
cables even before the Jenny Tonge's daughter case. I am not convinced that
fatality could not have happened if the fitters had followed regs. Does the
average householder think "oh I mustn't drill/nail in the installation
zones?" If the number of punctured pipes I have heard about is anything to
go by, most people don't think of such things as buried services when
putting up a fixture.

So given:
1) I know accidents have happened in the past.
2) It is quite difficult to get an electric shock from fixed wiring if
properly installed and used sensibly.
3) Putting in nails/screws is very common activity
4) Most casual DIYers won't think to check for the presence of wires.

it doesn't take a big lap of imagination to say:

it must be one of the major causes of injury in decent installations

Big cause of injury generally ? Absolutely not, but since when have the
regulators been concerned about relative risks? (See Part P for details).

replastering/redecoration. The fact the conduit is earthed (assuming it is
installed to Regs) would be an added safety feature too. The way the

I don't think under currents regs that you are allowed to rely on the
conduit for earthing, as opposed to having it earthed.

Dave

--

Some people use windows, others have a life.

"Dave Stanton" wrote in message
news

I don't think under currents regs that you are allowed to rely on the
conduit for earthing, as opposed to having it earthed.


I thought you could use the conduit as the CPC. (543-01- etc.), but it may
have changed since the 16th edition first came out. Personally, I'd use a
separate conductor anyway. However, the point I was trying to make was that
any length of metal conduit over 150mm has to be bonded to earth regardless
of whether it is used as the CPC or not.

I thought you could use the conduit as the CPC. (543-01- etc.), but it may
have changed since the 16th edition first came out. Personally, I'd use a
separate conductor anyway. However, the point I was trying to make was
that any length of metal conduit over 150mm has to be bonded to earth
regardless of whether it is used as the CPC or not.

Agreed, much better practice.

Dave

--

Some people use windows, others have a life.

"Dave Plowman (News)" wrote in message
...
In article ,
Malc wrote:
I was thinking that as most of the floors are likely to be ripped up I
might run steel conduit around as is done in commercial buildings and
use individual wires for L, N and E as is done in commercial buildings.
Would this be ok? I presume I'd have to use brown, blue and green/yellow
wires.

I'd say you've never worked with conduit? It's not easy, and *very* *very*
expensive. You'll also need a proper floor standing bender which also
doubles as a vice for threading it. Think several hundred pounds just for
that and the tools.

I have worked with conduit which is why I suggested it. I must admit to
never having bought any however as it's always been on commercial
installations. I just liked the idea of being able to run single core wires
easily around the place rather than T&E.

--
Malc

On Sun, 05 Dec 2004 21:03:32 GMT, "Malc"
wrote:


"Dave Plowman (News)" wrote in message
...
In article ,
Malc wrote:
I was thinking that as most of the floors are likely to be ripped up I
might run steel conduit around as is done in commercial buildings and
use individual wires for L, N and E as is done in commercial buildings.
Would this be ok? I presume I'd have to use brown, blue and green/yellow
wires.

I'd say you've never worked with conduit? It's not easy, and *very* *very*
expensive. You'll also need a proper floor standing bender which also
doubles as a vice for threading it. Think several hundred pounds just for
that and the tools.

I have worked with conduit which is why I suggested it. I must admit to
never having bought any however as it's always been on commercial
installations. I just liked the idea of being able to run single core wires
easily around the place rather than T&E.

OK.... so how about plastic?

This is very easy to work with and flexible enough to run through
joists if you wanted to do that. It must be at least 50mm from top
and bottom, though.

With any kind of conduit or trunking, you do have to be careful about
both the mechanical and electrical grouping. T&E is straightforward
in the sense that there are standard sizes and those for specific
circuit types, well known. There are also few main installation
situations in a house, e.g. being attached to masonry and in free air
but supported as in joist runs.
If you are going to use trunking and conduit then you do need to do
the sums and be careful not to stuff them too full or exceed the
allowances. The IEE On Site Guide among other publications has
tables and formulae for this.



--

..andy

To email, substitute .nospam with .gl

"Malc" wrote in message
. uk...
"Dave Plowman (News)" wrote in message
...
In article ,
Malc wrote:

I was thinking that as most of the floors are likely to be ripped up
I
might run steel conduit snip

I'd say you've never worked with conduit? snip

I have worked with conduit which is why I suggested it.
snip

That said it seems strange, IMO, that you would ask such a question then
!....

Dave Stanton wrote in message . ..
replastering/redecoration. The fact the conduit is earthed (assuming it is
installed to Regs) would be an added safety feature too. The way the

I don't think under currents regs that you are allowed to rely on the
conduit for earthing, as opposed to having it earthed.

Dave

You can but the Zs must be measured to ensure that your protection
operates within the required time, ie lights 5secs & "most" sockets
o.2 secs..
There is a technical expression used by electricians using the
installation method that you propose, it is "Oh **** its conduit"
Bob

In article ,
Andy Hall wrote:
If you are going to use trunking and conduit then you do need to do
the sums and be careful not to stuff them too full or exceed the
allowances. The IEE On Site Guide among other publications has
tables and formulae for this.

You also have to be careful where line and neutral ain't together as in
T&E. I well remember a gridswitch with fuses for lights where all the
lines were routed through one conduit and all the neutrals another. Got
quite hot...

--
*A backward poet writes inverse.*

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
Malc wrote:
I'd say you've never worked with conduit? It's not easy, and *very*
*very* expensive. You'll also need a proper floor standing bender
which also doubles as a vice for threading it. Think several hundred
pounds just for that and the tools.

I have worked with conduit which is why I suggested it. I must admit to
never having bought any however as it's always been on commercial
installations. I just liked the idea of being able to run single core
wires easily around the place rather than T&E.

You've worked with it but still don't mind the vast amount of extra work
to save pennies on cable? Fine.

--
*I'm not your type. I'm not inflatable.

Dave Plowman London SW
To e-mail, change noise into sound.

On Sun, 05 Dec 2004 21:03:32 GMT, "Malc"
strung together this:

I have worked with conduit which is why I suggested it.

You mean you put a length of PVC on a wall once. I think you'll find
that using galv tube everywhere is 10x harder than T&E, and PVC isn't
much better, (for domestic anyway).
--

SJW
A.C.S. Ltd
Please reply to group or use 'usenet' in email subject

You can but the Zs must be measured to ensure that your protection
operates within the required time, ie lights 5secs & "most" sockets o.2
secs..
There is a technical expression used by electricians using the
installation method that you propose, it is "Oh **** its conduit" Bob

Thats why my best practice would always be run a seperate wire, allowing
for derating, temp etc.

Dave

--

Some people use windows, others have a life.

Because I wanted to know about the legal side of it which I thought I'd
made plain. Still if you can't understand perhaps you shouldn't be
replying.

--
Malc

Because I wanted to know about the legal side of it which I thought I'd
made plain. Still if you can't understand perhaps you shouldn't be
replying.

--
Malc

On 7 Dec 2004 00:32:31 -0800, wrote:

Because I wanted to know about the legal side of it which I thought I'd
made plain. Still if you can't understand perhaps you shouldn't be
replying.

To be honest, Malcolm, I don't think it was so clear - certainly not
at the outset.

You said:

"Ok this is a bit hypothetical at present because we haven't bought
the building yet (and may never do if we can't find the owner).

We are thinking of restoring an old house and obviously I will be
doing the wiring myself and getting it inspected as there is no way
that I will be able to hide the fact that I'm doing it. I was thinking
that as most of the floors are likely to be ripped up I might run
steel conduit around as is one in commercial buildings and use
individual wires for L, N and E as is done in commercial buildings.
Would this be ok? I presume I'd have to use brown, blue and
green/yellow wires."

There was nothing in that which suggested that you had worked with
steel conduit before, and the only thing that suggested you had done
wiring at all before was the comment "obviously I will be doing the
wiring myself.." Even that wouldn't necessarily imply
experience. If you look back through old threads, you'd find that
quite often somebody new or fairly new will ask a question like this
and say that obviously they will do something - simply because they
believe that they can do anything that they care to tackle. That may
or may not be true, but there was nothing in your post to indicate
much different. When coupled with wanting to use steel conduit,
which is hardly the easiest material to use and certainly not
appropriate if one were a novice, people naturally started to ask why.

It wasn't until later that you introduced the point that you had
worked with it quite a bit and had done wiring etc. That's fine, but
the closing part of your original question was whether it would be OK.
That was fairly broad in the sense that it could have meant could the
job be done physically, technically or in accordance with wiring
regulations.

If you were only really asking about the last of these, then I'm
perplexed. If you are doing wiring and conduit work in a range of
commercial premises, wouldn't you be familiar with BS7671 anyway?

What is it that you were unsure about?





--

..andy

To email, substitute .nospam with .gl

In article .com,
wrote:
Because I wanted to know about the legal side of it which I thought I'd
made plain.

No. This is the first time you've mentioned it. Assuming it is you since
you're using a different address and no sig.

Still if you can't understand perhaps you shouldn't be
replying.

People reply to the question as they read it.

If you're asking is conduit legal in a house, what would be your guess
being so familiar with installing it?

--
*Therapy is expensive, poppin' bubble wrap is cheap! You choose.

Dave Plowman London SW
To e-mail, change noise into sound.

On 7 Dec 2004 00:32:09 -0800, strung
together this:

Because I wanted to know about the legal side of it

Then why didn't you say that. There is no law against wiring your
house in bell wire if you want.

which I thought I'd made plain.

No, you hadn't actually, re-read your posts.

Still if you can't understand perhaps you shouldn't be
replying.

What didn't I understand, the invisible ink that you were writing in?
On balance, I don't think you should actually be touching any wiring
at all, it doesn't sound as if you are familiar with any regulations
otherwise you wouldn't have to ask.
--

SJW
A.C.S. Ltd
Please reply to group or use 'usenet' in email subject