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Soil pipe through / over joists?

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Tommy Gilchrist

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Aug 25, 2004, 4:27:01 PM8/25/04
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When you need to start with "I know this is probably a stupid question
but..." you probably already know the answer.

I need to install a new bathroom upstairs which, due to a builder
letting us down, I'm going to have to plumb myself although I am going
to get a plumber in to QA the work before running water.

One question. I'm sticking the toliet beside an external wall with
easy access to an existing soil pipe. However the joists in the floor
run parallel to the external wall and there's one tight against the
wall.

I assume this means the soil pipe will have to go through the wall
above the floor level? Will the smaller waste pipes i.e. from the bath
and basin be able to go through the joists - they're about 200mm deep.

thanks

tommy

John Rumm

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Aug 25, 2004, 7:34:04 PM8/25/04
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Tommy Gilchrist wrote:

> One question. I'm sticking the toliet beside an external wall with
> easy access to an existing soil pipe. However the joists in the floor
> run parallel to the external wall and there's one tight against the
> wall.
>
> I assume this means the soil pipe will have to go through the wall
> above the floor level? Will the smaller waste pipes i.e. from the bath
> and basin be able to go through the joists - they're about 200mm deep.

Your toilet probably has a horizontal outlet anyway - designed to be
taken straight through the wall at a height of about 190mm above the
finished floor level.

The other pipes are probably simpler taken out above floor level as
well. Typically you should not make hole through joists that are more
than 10% of their total depth, although close to a wall, or in cases
where the joist span is relatively short you can.

--
Cheers,

John.

/=================================================================\
| Internode Ltd - http://www.internode.co.uk |
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| John Rumm - john(at)internode(dot)co(dot)uk |
\=================================================================/

Christian McArdle

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Aug 26, 2004, 5:19:48 AM8/26/04
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> I assume this means the soil pipe will have to go through the wall
> above the floor level?

That is the normal method of installation. To make the hole, ensure that you
hire a quality SDS drill with suitably sized diamond tipped core drill. This
will make a nice clean hole for you.

Christian.


Kalico

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Aug 26, 2004, 7:05:31 AM8/26/04
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Take any waste pipes (inc soil) above the joists. Water pipes can go
below.


Replace 'spam' with 'org' to reply

Tommy Gilchrist

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Aug 26, 2004, 1:34:15 PM8/26/04
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On Thu, 26 Aug 2004 12:05:31 +0100, Kalico <r...@kalico.spam> wrote:

>
>Take any waste pipes (inc soil) above the joists. Water pipes can go
>below.
>
>
>Replace 'spam' with 'org' to reply

Thanks for the feedback - the advice makes sense but do the waste
pipes for the bath and the shower (only doing the bath at this stage)
not need to be below the level of the plug hole?

Would this not mean you would have to raise the level of the plug hole
or are they far enough above ground level anyway?

In case you haven't guessed I'm no expert on plumbing and wouldn't be
at this at all if it wasn't an emergency (very pregnant wife / no
reliable plumber available for weeks)

Tommy

Tommy Gilchrist

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Aug 26, 2004, 1:34:16 PM8/26/04
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W/C soil pipes are 110mm I believe? Can you get a drill bit this size
or do you drill lots of smaller holes?

Thanks

tommy

chris French

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Aug 26, 2004, 5:38:39 PM8/26/04
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In message <ok7si01vld44v74u1...@4ax.com>, Tommy Gilchrist
<to...@delete.gilchristcs.the.com.needful> writes
You can get large core drills - basically like a hole saw for walls for
this sort of thing - but you won't do it with your B&D.
--
Chris French, Leeds

Lurch

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Aug 26, 2004, 5:57:42 PM8/26/04
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On Thu, 26 Aug 2004 18:34:16 +0100, Tommy Gilchrist
<to...@delete.gilchristcs.the.com.needful> strung together this:

>W/C soil pipes are 110mm I believe? Can you get a drill bit this size

Yes, if you're hiring one then the hire centre will be able to sort
you out with one of the correct size. Just tell them you want a
diamond core drill for a 110mm soil pipe.
--

SJW
A.C.S. Ltd

Kalico

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Aug 26, 2004, 5:57:31 PM8/26/04
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No worries about experience - we all started somewhere and I learn
something every single day. Often of not much value though.

From the bath plug hole, use a proper thing called a 'bath trap'.
This has a low profile so that the pipe that runs from it can be kept
above floor-board level.

Of course, this can then be dropped below floor level and run along
the floor/ceiling void if that is possible. Depends on the direction
of your joists/boards. DO NOT cut joist to run the waste from the
bath though. If they are not in-line to the direction you want to go
then run above floor.

Hope that helps.
Rob

Tommy Gilchrist

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Aug 27, 2004, 3:41:55 AM8/27/04
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Indeed it does. Thanks to all for the info.

tommy

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