Replacing downstairs bog - soil pipe problems

[Jon Taylor]

Dear fellow uk.d-i-y'ers,

I'm replacing the downstairs bog (which was a horrible nasty 1970's discoloured job) with a nice new closed couple verison. The new bog outlet sits about a foot back from where the old one was, so I'll need to put a bend into the existing soil pipe. I guess this must be quite common for diyers fitting a new bog.

So far I've ripped out the old bog. The soil pipe however is clay and runs vertically down from the bog about 3 feet, then has a 90 degree bend in it and runs into the drains. At the top of the pipe is a cement "collar" which is held on with putty and sits above the flooboards (It's never going to budge off the pipe!). I've ripped up the floorboards around the pipe and there is plenty of access - I can access the entire vertical stretch of the pipe.

So, how do I plumb in the new bog so it fits into the existing soil pipe? Presumably I will need to cut the existing clay pipe squarely off. I've read on this newgroup that I could: a) Use an angle grinder b) Use a soil pipe cutter tool hired from HSS (about 15 quid for a days hire) c) Carefully cut it using a hammer and chisel.

I feel a bit uneasy about using an angle grinder on a soil pipe - and also the hammer and chisel. Sounds a receipe for disaster, one slip and I have to start again! So I think that using the soil pipe cutter tool might be the best option. But how easy are these things to use? If I get this missus to hold the pipe to stop it flapping about, am I likely to knacker it up. Any tips for me on how to use it?

As for fitting it to the new bog, presumably I get a plastic adapter to connect inside the clay pipe and mastic it in. Then have a section of pipe with a bend in it, then connect to the 'P' trap?

Please help!

Cheers Jon

[The Natural Philosopher]

What I did on a plastic pipe in a similar situation is not a solution you can buy off the shelf. I used a small angle grinder disc bolted to something I had lying around and fitted it to an electric drill.

The cutter was then used INSIDE the pipe.

Its unguarded, and it needs strength to hold it as it wants to grab everywhere, but it worked.

[Set Square]

Are you planning to cut the clay pipe on the vertical bit, or on the horizontal bit after it's turned the corner? It's as well to minimise the number of bends. If the horizontal bit runs straight backwards so as to be under the new outlet, the best plan would be to shorten that, and to fit a new complete plastic vertical bit in the right place. Is the outlet on your new bog horizontal? If so, get a plastic bog outlet elbow with a vertical bit designed to fit *inside* a 110mm plastic soil pipe (e.g. Screwfix D15330). That way you can simply cut off your new vertical pipe at floor level with no extra fittings required. [You will, of course, need a fitting to join plastic to clay down on the horizontal bit (e.g. Screwfix D19914)].

With regard to cutting off the clay pipe - I certainly wouldn't use a hammer and chisel - that's a recipe for breaking it off in a very untidy way! I've got no experience of soil pipe cutters - but reckon that an angle grinder (with the right sort of disc) should do the job well enough.

[Alan]

I've just done very similar stuff but outside 3 foot under my drive. I used an angle grinder with a diamond cutting disc in it to cut through 2 clay pipes. Easy enough, clean cut. I used adaptors bought from B&Q to convert clay to plastic, then all new pipework in plastic. No mastic required as adaptors have rubber seals which seal over the outside of the clay pipe. I just had to 'lube them a little with washing-up liquid to encourage them to slip over.

Pipework was easy enough to do, but exposing pipework and filing in hole afterwards took ages!

Alan.

[John Woodhall]

I used an angle grinder with a diamond disc, as you say, if access is good then a 41/2 inch grinder is all thats needed, B&Q were selling a bosch jobbie with a free diamond disc for 20 quid. May be more economical to buy this which has many uses than hire to use something once.

[Andrew Gabriel]

As someone else who took their avacardo bathroom suite to the tip a few months ago, to join the variety of other colours there, I can't help thinking that in a couple of years time, they'll be all the rage again. Perhaps I should have stored it in the loft ;-)

[John Rumm]

Not sure if you are going to have space to use a soil pipe cutter. These are usually quite long (approx 4' handles) and need to work perpendicular to the pipe you are cutting. They have a toothed chain at the business end. You lap the chain round the pipe and then hook the end over a lug on jaws of the tool. You then squeeze the handles of the cutter, and this pulls the chain very tightly round the pipe forcing the teeth on the chain into the outer surface of the pipe. The pipe should then (in theory) snap with a nice square ended break where the chain was.

They work well on nice new soil pipe you get from a builders merchant - they are less predictable on old salt glazed pipes, and you may find you need several stabs at a cut to get a clean break.

With older pipes or confined access you may well find a small angle grinder with masonary disc is actually easier.

You can get adaption collers with rubber O ring in them that will let you join to the old pipe and then carry on in plastic. Not sure on what the regulations are regarding use of mastics on these things though.

[Alan]

John,

That's exactly the discs I used - got them in B&Q a few weeks back as seemed like a good deal. Work very well on wall tiles also.

Al.

[Peter Taylor]

Jon, the drain collar was originally intended for an S trap pan complying with the old BS, with a separate cistern and a flush pipe. Might even have been with a high level cistern. Replacement with a close coupled suite is problematic, as you've found. You can still get S trap pans (Twyford Classic for instance). It would save you needing to cut off the collar.

Peter

[Set Square]

Except that it's in the wrong place (too far from the wall) for a close-coupled pan - and the OP specifically wants close-coupled.

[Zymurgy]

I bought a nice, new white bog to replace the old one I have. Then the girlfriend says, oh, I quite like the colour of the old one (pink).

Bloody wimmin.

Now I have to store the bleeding thing somewhere, I bought it a while ago, not sure they'll take it back now .. :-((

Cheers

Paul.

[Owain]

"Zymurgy" wrote | I bought a nice, new white bog to replace the old one I have. | Then the girlfriend says, oh, I quite like the colour of the | old one (pink). | Bloody wimmin. | Now I have to store the bleeding thing somewhere, I bought it | a while ago, not sure they'll take it back now .. :-((

Replace both loo and girlfriend. Problem solved.

Owain

[Zymurgy]

"Owain" wrote

It's a compelling argument :)

P.