Installing an upstairs toilet

[JMC]

I have an upstairs bedroom with ensuite shower & basin room, to which I want to add a toilet.

Assuming the water supply is OK, presumably the only problem is running a 4-inch waste pipe from the new toilet and connecting it to the same waste pipe system my existing downstairs toilet uses.

The pipe would run beneath the floorboards, parallel to the joists. There is a space of at least 4 inches between the upstairs floorboards and the downstairs ceiling (the U-bend is above the floorboards, right?), but the pipe would have to run at least 5 metres horizontally from beneath the new toilet before it could connect up to the existing waste system. There would be no slope.

Would this distance be a problem, do you know?

Thanks for any help.

[Lurch]

On 12 May 2004 03:45:21 -0700, in uk.d-i-y [e-mail] (JMC) strung together this:

Then you can't do it, liquids, or semi liquidy objects, only flow downhill. I would imagine you'd have 6" joists min, that's ~50mm fall over

5000mm. 1:100, in other words.

[Grunff]

No slope == no pipe.

There is always a way to get a sufficient gradient. With our ensuite shower room, we built the floor so that it's 14" higher than the main bedroom floor. You need a 1:50 - 1:100 gradient, the steeper the better.

[Christian McArdle]

You're in Saniflo territory, unless you can run another complete soil pipe to sewers outside. Saniflos work reasonably well in en-suites, as there are no children or visitors to clog them with entire bog rolls or tampons.

Christian.

[BigWallop]

Not really feasible to run solid waste in a horizontal pipe as it gets easily stuck to the inside edges, so it's best to have as steep a running angle as possible so the whole pipe flushed after being used.

Does the existing sewer and soil pipe from the downstairs loo run under the house ? It might be possible to pick up the sewer system again at the other end of the property if you know where it goes.

[troubleinstore]

Why didn't someone tell the person who modernisewd my home all those years ago about pipes under floorboards. Infact, houses on the street where I live have been upgraded by housing accociations recently and they have the bathroom in the middle of the house like mine and the pipes under the floor going to the main stench pipe some 9 foot away.

-- troubleinstore

[Christian McArdle]

Ah, but there may be wider joists. If the joists were 220mm, for example, and a 100mm soil pipe, that would give 120mm fall over 2.7m, which is around

1:22, which is, AIUI, the recommended fall. It is approximately 2.5 degrees, which is why they invented the 92.5 degree T.

Christian.

[Jonathan Pearson]

This is a total misconception, just like your pipes once you get underground (but can't see) - they are not as steep as possible but at a very gentle slope!!, their is an optimum slope which is around 1:50 i.e over 5m a 100mm drop (please check the exact figures in build regs), if you have a steep angle the water flows too fast and the solids are left high and dry, if the solids dry out and stick the next flush may not move it, hence you may eventually get a blockage!, the idea been behind a relatively shallow slope is that the water moves much more slowly and carries the solids along with it, the optimum is just before the solids drop out of suspension, hence why building regs have a slope from something like 1:20 to 1:100, i.e a gentle slope

Jon

[Owain]

"Jonathan Pearson" wrote | This is a total misconception, just like your pipes once you get | underground (but can't see) - they are not as steep as possible | but at a very gentle slope!!, their is an optimum slope which | is around 1:50 i.e over 5m a 100mm drop (please check the exact | figures in build regs), if you have a steep angle the water | flows too fast and the solids are left high and dry, if the solids | dry out and stick the next flush may not move it, hence you may | eventually get a blockage!,

And if you watched Life of Grime the other night, you don't want a blockage. (Especially one with seventeen storeys of other people's "solids" coming up your S-bend.)

Owain

[BigWallop]

I must select my wording more appropriately. I must select my wording more appropriately. I must select my wording more appropriately. I must select my wording more appropriately. I must select my wording more appropriately. :-))

[The Natural Philosopher]

An insuperable one, with no slope.

[The Natural Philosopher]

Best soil stack story I ever heard was from the building manager of a 15 story luxury hotel in Africa.

The whole hotel expended enough in the african heat to pop the ( in the air conditioned cool interior) stack joints on the lower floors.....

[BigWallop]

EeeeYuckie !!! Sounds like the type of hotel were you write home and say "Wish you where here and not me". :-))

[The Natural Philosopher]

Actualy not. Upwards of the 10th floor it was extremely nice. I was there to intall a disco in the very top floor night club...we got free broiled lobsters and salad all the time.. :-)

>

[Jonathan Pearson]

and I must learn not to post after a bad day at work!! - apologies for the slightly aggressive post!! Jon

[N. Thornton]

This doesnt seem insuperable by any means. I'd consider the possible option of cutting a groove in the ceiling below to allow your pipe to get adequate fall, then your options are:

1. lower the ceiling a couple of inches
2. Slope one edge of the ceiling very slightly
3. box it, my least favourite option
4. Other more creative plasterwork or woodwork.
5. Cupboard or shelf that makes the pipe non visible

Or of course use a loo with an above floor pipe.

Regards, NT